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<pre class="prettyprint lang-js"><span id='String'>/**
</span> * @class String
*
* `String` is a global object that may be used to construct String instances.
*
* String objects may be created by calling the constructor `new String()`. The `String` object wraps
* JavaScript's string primitive data type with the methods described below. The global function
* `String()` can also be called without new in front to create a primitive string. String literals in
* JavaScript are primitive strings.
*
* Because JavaScript automatically converts between string primitives and String objects, you can call
* any of the methods of the `String` object on a string primitive. JavaScript automatically converts the
* string primitive to a temporary `String` object, calls the method, then discards the temporary String
* object. For example, you can use the `String.length` property on a string primitive created from a
* string literal:
*
* s_obj = new String(s_prim = s_also_prim = "foo");
*
* s_obj.length; // 3
* s_prim.length; // 3
* s_also_prim.length; // 3
* 'foo'.length; // 3
* "foo".length; // 3
*
* (A string literal is denoted with single or double quotation marks.)
*
* String objects can be converted to primitive strings with the `valueOf` method.
*
* String primitives and String objects give different results when evaluated as JavaScript. Primitives
* are treated as source code; String objects are treated as a character sequence object. For example:
*
* s1 = "2 + 2"; // creates a string primitive
* s2 = new String("2 + 2"); // creates a String object
* eval(s1); // returns the number 4
* eval(s2); // returns the string "2 + 2"
* eval(s2.valueOf()); // returns the number 4
*
* # Character access
*
* There are two ways to access an individual character in a string. The first is the `charAt` method:
*
* return 'cat'.charAt(1); // returns "a"
*
* The other way is to treat the string as an array, where each index corresponds to an individual
* character:
*
* return 'cat'[1]; // returns "a"
*
* The second way (treating the string as an array) is not part of ECMAScript 3. It is a JavaScript and
* ECMAScript 5 feature.
*
* In both cases, attempting to set an individual character won't work. Trying to set a character
* through `charAt` results in an error, while trying to set a character via indexing does not throw an
* error, but the string itself is unchanged.
*
* # Comparing strings
*
* C developers have the `strcmp()` function for comparing strings. In JavaScript, you just use the less-
* than and greater-than operators:
*
* var a = "a";
* var b = "b";
* if (a < b) // true
* print(a + " is less than " + b);
* else if (a > b)
* print(a + " is greater than " + b);
* else
* print(a + " and " + b + " are equal.");
*
* A similar result can be achieved using the `localeCompare` method inherited by `String` instances.
*
* <div class="notice">
* Documentation for this class comes from <a href="https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/String">MDN</a>
* and is available under <a href="http://creativecommons.org/licenses/by-sa/2.0/">Creative Commons: Attribution-Sharealike license</a>.
* </div>
*/
<span id='String-method-constructor'>/**
</span> * @method constructor
* Creates new String object.
* @param {Object} value The value to wrap into String object.
*/
//Methods
<span id='String-method-fromCharCode'>/**
</span> * @method fromCharCode
* Returns a string created by using the specified sequence of Unicode values.
*
* This method returns a string and not a `String` object.
*
* Because `fromCharCode` is a static method of `String`, you always use it as `String.fromCharCode()`,
* rather than as a method of a `String` object you created.
*
* Although most common Unicode values can be represented in a fixed width system/with one number (as
* expected early on during JavaScript standardization) and `fromCharCode()` can be used to return a
* single character for the most common values (i.e., UCS-2 values which are the subset of UTF-16 with
* the most common characters), in order to deal with ALL legal Unicode values, `fromCharCode()` alone
* is inadequate. Since the higher code point characters use two (lower value) "surrogate" numbers to
* form a single character, `fromCharCode()` can be used to return such a pair and thus adequately
* represent these higher valued characters.
*
* Be aware, therefore, that the following utility function to grab the accurate character even for
* higher value code points, may be returning a value which is rendered as a single character, but
* which has a string count of two (though usually the count will be one).
*
* // String.fromCharCode() alone cannot get the character at such a high code point
* // The following, on the other hand, can return a 4-byte character as well as the
* // usual 2-byte ones (i.e., it can return a single character which actually has
* // a string length of 2 instead of 1!)
* alert(fixedFromCharCode(0x2F804)); // or 194564 in decimal
*
* function fixedFromCharCode (codePt) {
* if (codePt > 0xFFFF) {
* codePt -= 0x10000;
* return String.fromCharCode(0xD800 + (codePt >> 10), 0xDC00 +
* (codePt & 0x3FF));
* }
* else {
* return String.fromCharCode(codePt);
* }
* }
*
* The following example returns the string "ABC".
*
* String.fromCharCode(65,66,67)
*
* @param {Number} num1, ..., numN A sequence of numbers that are Unicode values.
* @return {String} String containing characters from encoding.
*/
//Properties
<span id='String-property-length'>/**
</span> * @property {Number} length
* Reflects the length of the string.
*
* This property returns the number of code units in the string. UTF-16, the string format used by JavaScript, uses a single 16-bit
* code unit to represent the most common characters, but needs to use two code units for less commonly-used characters, so it's
* possible for the value returned by `length` to not match the actual number of characters in the string.
*
* For an empty string, `length` is 0.
*
* var x = "Netscape";
* var empty = "";
*
* console.log("Netspace is " + x.length + " code units long");
* console.log("The empty string is has a length of " + empty.length); // should be 0
*/
//Methods
<span id='String-method-charAt'>/**
</span> * @method charAt
* Returns the character at the specified index.
*
* Characters in a string are indexed from left to right. The index of the first character is 0, and
* the index of the last character in a string called `stringName` is `stringName.length - 1`. If the
* index you supply is out of range, JavaScript returns an empty string.
*
* The following example displays characters at different locations in the string "Brave new world":
*
* var anyString="Brave new world";
*
* document.writeln("The character at index 0 is '" + anyString.charAt(0) + "'");
* document.writeln("The character at index 1 is '" + anyString.charAt(1) + "'");
* document.writeln("The character at index 2 is '" + anyString.charAt(2) + "'");
* document.writeln("The character at index 3 is '" + anyString.charAt(3) + "'");
* document.writeln("The character at index 4 is '" + anyString.charAt(4) + "'");
* document.writeln("The character at index 999 is '" + anyString.charAt(999) + "'");
*
* These lines display the following:
*
* The character at index 0 is 'B'
* The character at index 1 is 'r'
* The character at index 2 is 'a'
* The character at index 3 is 'v'
* The character at index 4 is 'e'
* The character at index 999 is ''
*
* The following provides a means of ensuring that going through a string loop always provides a whole
* character, even if the string contains characters that are not in the Basic Multi-lingual Plane.
*
* var str = 'A\uD87E\uDC04Z'; // We could also use a non-BMP character directly
* for (var i=0, chr; i < str.length; i++) {
* if ((chr = getWholeChar(str, i)) === false) {continue;} // Adapt this line at the top of
* each loop, passing in the whole string and the current iteration and returning a variable to
* represent the individual character
* alert(chr);
* }
*
* function getWholeChar (str, i) {
* var code = str.charCodeAt(i);
*
* if (isNaN(code)) {
* return ''; // Position not found
* }
* if (code < 0xD800 || code > 0xDFFF) {
* return str.charAt(i);
* }
* if (0xD800 <= code && code <= 0xDBFF) { // High surrogate (could change last hex to 0xDB7F
* to treat high private surrogates as single characters)
* if (str.length <= (i+1)) {
* throw 'High surrogate without following low surrogate';
* }
* var next = str.charCodeAt(i+1);
* if (0xDC00 > next || next > 0xDFFF) {
* throw 'High surrogate without following low surrogate';
* }
* return str.charAt(i)+str.charAt(i+1);
* }
* // Low surrogate (0xDC00 <= code && code <= 0xDFFF)
* if (i === 0) {
* throw 'Low surrogate without preceding high surrogate';
* }
* var prev = str.charCodeAt(i-1);
* if (0xD800 > prev || prev > 0xDBFF) { // (could change last hex to 0xDB7F to treat high private
* surrogates as single characters)
* throw 'Low surrogate without preceding high surrogate';
* }
* return false; // We can pass over low surrogates now as the second component in a pair which we
* have already processed
* }
*
* While the second example may be more frequently useful for those wishing to support non-BMP
* characters (since the above does not require the caller to know where any non-BMP character might
* appear), in the event that one _does_ wish, in choosing a character by index, to treat the surrogate
* pairs within a string as the single characters they represent, one can use the following:
*
* function fixedCharAt (str, idx) {
* var ret = '';
* str += '';
* var end = str.length;
*
* var surrogatePairs = /[\uD800-\uDBFF][\uDC00-\uDFFF]/g;
* while ((surrogatePairs.exec(str)) != null) {
* var li = surrogatePairs.lastIndex;
* if (li - 2 < idx) {
* idx++;
* }
* else {
* break;
* }
* }
*
* if (idx >= end || idx < 0) {
* return '';
* }
*
* ret += str.charAt(idx);
*
* if (/[\uD800-\uDBFF]/.test(ret) && /[\uDC00-\uDFFF]/.test(str.charAt(idx+1))) {
* ret += str.charAt(idx+1); // Go one further, since one of the "characters" is part of a
* surrogate pair
* }
* return ret;
* }
*
* @param {Number} index An integer between 0 and 1 less than the length of the string.
* @return {String} Individual character from string.
*/
<span id='String-method-charCodeAt'>/**
</span> * @method charCodeAt
* Returns a number indicating the Unicode value of the character at the given index.
*
* Unicode code points range from 0 to 1,114,111. The first 128 Unicode code points are a direct match
* of the ASCII character encoding.
*
* Note that `charCodeAt` will always return a value that is less than 65,536. This is because the
* higher code points are represented by a pair of (lower valued) "surrogate" pseudo-characters which
* are used to comprise the real character. Because of this, in order to examine or reproduce the full
* character for individual characters of value 65,536 and above, for such characters, it is necessary
* to retrieve not only `charCodeAt(i)`, but also `charCodeAt(i+1)` (as if examining/reproducing a
* string with two letters). See example 2 and 3 below.
*
* `charCodeAt` returns `NaN` if the given index is not greater than 0 or is greater than the length of
* the string.
*
* Backward Compatibility with JavaScript 1.2
*
* The `charCodeAt` method returns a number indicating the ISO-Latin-1 codeset value of the character
* at the given index. The ISO-Latin-1 codeset ranges from 0 to 255. The first 0 to 127 are a direct
* match of the ASCII character set.
*
* Example 1: Using `charCodeAt`
*
* The following example returns 65, the Unicode value for A.
*
* "ABC".charCodeAt(0) // returns 65
*
* Example 2: Fixing `charCodeAt` to handle non-Basic-Multilingual-Plane characters if their presence
* earlier in the string is unknown
*
* This version might be used in for loops and the like when it is unknown whether non-BMP characters
* exist before the specified index position.
*
* function fixedCharCodeAt (str, idx) {
* // ex. fixedCharCodeAt ('\uD800\uDC00', 0); // 65536
* // ex. fixedCharCodeAt ('\uD800\uDC00', 1); // 65536
* idx = idx || 0;
* var code = str.charCodeAt(idx);
* var hi, low;
* if (0xD800 <= code && code <= 0xDBFF) { // High surrogate (could change last hex to 0xDB7F to treat high private surrogates as single characters)
* hi = code;
* low = str.charCodeAt(idx+1);
* if (isNaN(low)) {
* throw 'High surrogate not followed by low surrogate in fixedCharCodeAt()';
* }
* return ((hi - 0xD800) * 0x400) + (low - 0xDC00) + 0x10000;
* }
* if (0xDC00 <= code && code <= 0xDFFF) { // Low surrogate
* // We return false to allow loops to skip this iteration since should have already handled
* high surrogate above in the previous iteration
* return false;
* }
* return code;
* }
*
* Example 3: Fixing `charCodeAt` to handle non-Basic-Multilingual-Plane characters if their presence
* earlier in the string is known
*
* function knownCharCodeAt (str, idx) {
* str += '';
* var code,
* end = str.length;
*
* var surrogatePairs = /[\uD800-\uDBFF][\uDC00-\uDFFF]/g;
* while ((surrogatePairs.exec(str)) != null) {
* var li = surrogatePairs.lastIndex;
* if (li - 2 < idx) {
* idx++;
* }
* else {
* break;
* }
* }
*
* if (idx >= end || idx < 0) {
* return NaN;
* }
*
* code = str.charCodeAt(idx);
*
* var hi, low;
* if (0xD800 <= code && code <= 0xDBFF) {
* hi = code;
* low = str.charCodeAt(idx+1); // Go one further, since one of the "characters" is part of
* a surrogate pair
* return ((hi - 0xD800) * 0x400) + (low - 0xDC00) + 0x10000;
* }
* return code;
* }
*
* @param {Number} index An integer greater than 0 and less than the length of the string; if it is
* not a number, it defaults to 0.
* @return {Number} Value between 0 and 65535.
*/
<span id='String-method-concat'>/**
</span> * @method concat
* Combines the text of two strings and returns a new string.
*
* `concat` combines the text from one or more strings and returns a new string. Changes to the text in
* one string do not affect the other string.
*
* The following example combines strings into a new string.
*
* var hello = "Hello, ";
* console.log(hello.concat("Kevin", " have a nice day.")); // Hello, Kevin have a nice day.
*
* @param {String} string2...stringN
* @return {String} Result of both strings.
*/
<span id='String-method-indexOf'>/**
</span> * @method indexOf
* Returns the index within the calling `String` object of the first occurrence of the specified value,
* or -1 if not found.
*
* Characters in a string are indexed from left to right. The index of the first character is 0, and the index of the last character
* of a string called `stringName` is `stringName.length - 1`.
*
* "Blue Whale".indexOf("Blue") // returns 0
* "Blue Whale".indexOf("Blute") // returns -1
* "Blue Whale".indexOf("Whale",0) // returns 5
* "Blue Whale".indexOf("Whale",5) // returns 5
* "Blue Whale".indexOf("",9) // returns 9
* "Blue Whale".indexOf("",10) // returns 10
* "Blue Whale".indexOf("",11) // returns 10
*
* The `indexOf` method is case sensitive. For example, the following expression returns -1:
*
* "Blue Whale".indexOf("blue")
*
* Note that '0' doesn't evaluate to true and '-1' doesn't evaluate to false. Therefore, when checking if a specific string exists
* within another string the correct way to check would be:
*
* "Blue Whale".indexOf("Blue") != -1 // true
* "Blue Whale".indexOf("Bloe") != -1 // false
*
* The following example uses indexOf and lastIndexOf to locate values in the string "Brave new world".
*
* var anyString="Brave new world"
*
* document.write("<P>The index of the first w from the beginning is " + anyString.indexOf("w")) // Displays 8
* document.write("<P>The index of the first w from the end is " + anyString.lastIndexOf("w")) // Displays 10
* document.write("<P>The index of 'new' from the beginning is " + anyString.indexOf("new")) // Displays 6
* document.write("<P>The index of 'new' from the end is " + anyString.lastIndexOf("new")) // Displays 6
*
* The following example defines two string variables. The variables contain the same string except that the second string contains
* uppercase letters. The first `writeln` method displays 19. But because the `indexOf` method is case sensitive, the string
* "cheddar" is not found in `myCapString`, so the second `writeln` method displays -1.
*
* myString="brie, pepper jack, cheddar"
* myCapString="Brie, Pepper Jack, Cheddar"
* document.writeln('myString.indexOf("cheddar") is ' + myString.indexOf("cheddar"))
* document.writeln('<P>myCapString.indexOf("cheddar") is ' + myCapString.indexOf("cheddar"))
*
* The following example sets count to the number of occurrences of the letter x in the string str:
*
* count = 0;
* pos = str.indexOf("x");
* while ( pos != -1 ) {
* count++;
* pos = str.indexOf("x",pos+1);
* }
*
* @param {String} searchValue A string representing the value to search for.
* @param {Number} fromIndex The location within the calling string to start the search from. It can be any integer between 0 and
* the length of the string. The default value is 0.
* @return {Number} Position of specified value or -1 if not found.
*/
<span id='String-method-lastIndexOf'>/**
</span> * @method lastIndexOf
* Returns the index within the calling String object of the last occurrence of
* the specified value, or -1 if not found. The calling string is searched
* backward, starting at fromIndex.
*
* Characters in a string are indexed from left to right. The index of the first character is 0, and the index of the last character
* is `stringName.length - 1`.
*
* "canal".lastIndexOf("a") // returns 3
* "canal".lastIndexOf("a",2) // returns 1
* "canal".lastIndexOf("a",0) // returns -1
* "canal".lastIndexOf("x") // returns -1
*
* The `lastIndexOf` method is case sensitive. For example, the following expression returns -1:
*
* "Blue Whale, Killer Whale".lastIndexOf("blue")
*
* The following example uses `indexOf` and `lastIndexOf` to locate values in the string "`Brave new world`".
*
* var anyString="Brave new world"
*
* // Displays 8
* document.write("<P>The index of the first w from the beginning is " +
* anyString.indexOf("w"))
* // Displays 10
* document.write("<P>The index of the first w from the end is " +
* anyString.lastIndexOf("w"))
* // Displays 6
* document.write("<P>The index of 'new' from the beginning is " +
* anyString.indexOf("new"))
* // Displays 6
* document.write("<P>The index of 'new' from the end is " +
* anyString.lastIndexOf("new"))
*
* @param {String} searchValue A string representing the value to search for.
* @param {Number} fromIndex The location within the calling string to start the search from, indexed from left to right. It can
* be any integer between 0 and the length of the string. The default value is the length of the string.
* @return {Number}
*/
<span id='String-method-localeCompare'>/**
</span> * @method localeCompare
* Returns a number indicating whether a reference string comes before or after or is the same as the
* given string in sort order.
*
* Returns a number indicating whether a reference string comes before or after or is the same as the
* given string in sort order. Returns -1 if the string occurs earlier in a sort than `compareString`,
* returns 1 if the string occurs afterwards in such a sort, and returns 0 if they occur at the same
* level.
*
* The following example demonstrates the different potential results for a string occurring before,
* after, or at the same level as another:
*
* alert('a'.localeCompare('b')); // -1
* alert('b'.localeCompare('a')); // 1
* alert('b'.localeCompare('b')); // 0
*
* @param {String} compareString The string against which the referring string is comparing.
* @return {Number} Returns -1 if the string occurs earlier in a sort than
* compareString, returns 1 if the string occurs afterwards in such a sort, and
* returns 0 if they occur at the same level.
*/
<span id='String-method-match'>/**
</span> * @method match
* Used to match a regular expression against a string.
*
* If the regular expression does not include the `g` flag, returns the same result as `regexp.exec(string)`.
*
* If the regular expression includes the `g` flag, the method returns an Array containing all matches. If there were no matches,
* the method returns `null`.
*
* The returned {@link Array} has an extra `input` property, which contains the regexp that generated it as a result. In addition,
* it has an `index` property, which represents the zero-based index of the match in the string.
*
* In the following example, `match` is used to find "Chapter" followed by 1 or more numeric characters followed by a decimal point
* and numeric character 0 or more times. The regular expression includes the `i` flag so that case will be ignored.
*
* str = "For more information, see Chapter 3.4.5.1";
* re = /(chapter \d+(\.\d)*)/i;
* found = str.match(re);
* document.write(found);
*
* This returns the array containing Chapter 3.4.5.1,Chapter 3.4.5.1,.1
*
* "`Chapter 3.4.5.1`" is the first match and the first value remembered from `(Chapter \d+(\.\d)*)`.
*
* "`.1`" is the second value remembered from `(\.\d)`.
*
* The following example demonstrates the use of the global and ignore case flags with `match`. All letters A through E and a
* through e are returned, each its own element in the array
*
* var str = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
* var regexp = /[A-E]/gi;
* var matches_array = str.match(regexp);
* document.write(matches_array);
*
* `matches_array` now equals `['A', 'B', 'C', 'D', 'E', 'a', 'b', 'c', 'd', 'e']`.
*
* @param {RegExp} regexp A {@link RegExp} object. If a non-RegExp object `obj` is passed, it is
* implicitly converted to a RegExp by using `new RegExp(obj)`.
* @return {Array} Contains results of the match (if any).
*/
<span id='String-method-replace'>/**
</span> * @method replace
* Used to find a match between a regular expression and a string, and to replace the matched substring
* with a new substring.
*
* This method does not change the `String` object it is called on. It simply returns a new string.
*
* To perform a global search and replace, either include the `g` flag in the regular expression or if
* the first parameter is a string, include `g` in the flags parameter.
*
* The replacement string can include the following special replacement patterns:
*
* | Pattern | Inserts
* |:--------------|:--------------------------------------------------------------------------------------
* | `$$` | Inserts a `$`.
* | `$&` | Inserts the matched substring.
* | `$`` | Inserts the portion of the string that precedes the matched substring.
* | `$'` | Inserts the portion of the string that follows the matched substring.
* | `$n` or `$nn` | Where `n` or `nn` are decimal digits, inserts the _n_th parenthesized submatch string, provided the first
* | | argument was a `RegExp` object.
*
* You can specify a function as the second parameter. In this case, the function will be invoked after the match has been
* performed. The function's result (return value) will be used as the replacement string. (Note: the above-mentioned special
* replacement patterns do not apply in this case.) Note that the function will be invoked multiple times for each full match to be
* replaced if the regular expression in the first parameter is global.
*
* The arguments to the function are as follows:
*
* | Possible Name | Supplied Value
* |:--------------|:--------------------------------------------------------------------------------------
* | `str` | The matched substring. (Corresponds to `$&` above.)
* | `p1, p2, ...` | The _n_th parenthesized submatch string, provided the first argument to replace was a `RegExp` object.
* | | (Correspond to $1, $2, etc. above.)
* | `offset` | The offset of the matched substring within the total string being examined. (For example, if the total string
* | | was "`abcd`", and the matched substring was "`bc`", then this argument will be 1.)
* | `s` | The total string being examined.
*
* (The exact number of arguments will depend on whether the first argument was a `RegExp` object and, if so, how many parenthesized
* submatches it specifies.)
*
* The following example will set `newString` to "`XXzzzz - XX , zzzz`":
*
* function replacer(str, p1, p2, offset, s)
* {
* return str + " - " + p1 + " , " + p2;
* }
* var newString = "XXzzzz".replace(/(X*)(z*)/, replacer);
*
* In the following example, the regular expression includes the global and ignore case flags which permits replace to replace each
* occurrence of 'apples' in the string with 'oranges'.
*
* var re = /apples/gi;
* var str = "Apples are round, and apples are juicy.";
* var newstr = str.replace(re, "oranges");
* print(newstr);
*
* In this version, a string is used as the first parameter and the global and ignore case flags are specified in the flags
* parameter.
*
* var str = "Apples are round, and apples are juicy.";
* var newstr = str.replace("apples", "oranges", "gi");
* print(newstr);
*
* Both of these examples print "oranges are round, and oranges are juicy."
*
* In the following example, the regular expression is defined in replace and includes the ignore case flag.
*
* var str = "Twas the night before Xmas...";
* var newstr = str.replace(/xmas/i, "Christmas");
* print(newstr);
*
* This prints "Twas the night before Christmas..."
*
* The following script switches the words in the string. For the replacement text, the script uses the $1 and $2 replacement
* patterns.
*
* var re = /(\w+)\s(\w+)/;
* var str = "John Smith";
* var newstr = str.replace(re, "$2, $1");
* print(newstr);
*
* This prints "Smith, John".
*
* In this example, all occurrences of capital letters in the string are converted to lower case, and a hyphen is inserted just
* before the match location. The important thing here is that additional operations are needed on the matched item before it is
* given back as a replacement.
*
* The replacement function accepts the matched snippet as its parameter, and uses it to transform the case and concatenate the
* hyphen before returning.
*
* function styleHyphenFormat(propertyName)
* {
* function upperToHyphenLower(match)
* {
* return '-' + match.toLowerCase();
* }
* return propertyName.replace(/[A-Z]/, upperToHyphenLower);
* }
*
* Given `styleHyphenFormat('borderTop')`, this returns 'border-top'.
*
* Because we want to further transform the _result_ of the match before the final substitution is made, we must use a function.
* This forces the evaluation of the match prior to the `toLowerCase()` method. If we had tried to do this using the match without a
* function, the `toLowerCase()` would have no effect.
*
* var newString = propertyName.replace(/[A-Z]/, '-' + '$&'.toLowerCase()); // won't work
*
* This is because `'$&'.toLowerCase()` would be evaluated first as a string literal (resulting in the same `'$&'`) before using the
* characters as a pattern.
*
* The following example replaces a Fahrenheit degree with its equivalent Celsius degree. The Fahrenheit degree should be a number
* ending with F. The function returns the Celsius number ending with C. For example, if the input number is 212F, the function
* returns 100C. If the number is 0F, the function returns -17.77777777777778C.
*
* The regular expression `test` checks for any number that ends with F. The number of Fahrenheit degree is accessible to the
* function through its second parameter, `p1`. The function sets the Celsius number based on the Fahrenheit degree passed in a
* string to the `f2c` function. `f2c` then returns the Celsius number. This function approximates Perl's `s///e` flag.
*
* function f2c(x)
* {
* function convert(str, p1, offset, s)
* {
* return ((p1-32) * 5/9) + "C";
* }
* var s = String(x);
* var test = /(\d+(?:\.\d*)?)F\b/g;
* return s.replace(test, convert);
* }
*
* @param {String/RegExp} pattern Either a string or regular expression pattern to search for.
*
* @param {String/Function} replacement Either string or function:
*
* - The String to replace the `pattern` with. Number of special replacement patterns are supported;
* see the "Specifying a string as a parameter" section above.
* - A function to be invoked to create the replacement.
* The arguments supplied to this function are described in the "Specifying a function as a parameter"
* section above.
*
* @return {String} String of matched replaced items.
*/
<span id='String-method-search'>/**
</span> * @method search
* Executes the search for a match between a regular expression and a specified string.
*
* If successful, search returns the index of the regular expression inside the string. Otherwise, it
* returns -1.
*
* When you want to know whether a pattern is found in a string use search (similar to the regular
* expression `test` method); for more information (but slower execution) use `match` (similar to the
* regular expression `exec` method).
*
* The following example prints a message which depends on the success of the test.
*
* function testinput(re, str){
* if (str.search(re) != -1)
* midstring = " contains ";
* else
* midstring = " does not contain ";
* document.write (str + midstring + re);
* }
*
* @param {RegExp} regexp A regular expression object. If a non-RegExp object obj is passed, it is
* implicitly converted to a RegExp by using `new RegExp(obj)`.
* @return {Number} If successful, search returns the index of the regular
* expression inside the string. Otherwise, it returns -1.
*/
<span id='String-method-slice'>/**
</span> * @method slice
* Extracts a section of a string and returns a new string.
*
* `slice` extracts the text from one string and returns a new string. Changes to the text in one
* string do not affect the other string.
*
* `slice` extracts up to but not including `endSlice`. `string.slice(1,4)` extracts the second
* character through the fourth character (characters indexed 1, 2, and 3).
*
* As a negative index, `endSlice` indicates an offset from the end of the string. `string.slice(2,-1)`
* extracts the third character through the second to last character in the string.
*
* The following example uses slice to create a new string.
*
* // assumes a print function is defined
* var str1 = "The morning is upon us.";
* var str2 = str1.slice(4, -2);
* print(str2);
*
* This writes:
*
* morning is upon u
*
* @param {Number} beginSlice The zero-based index at which to begin extraction.
* @param {Number} endSlice The zero-based index at which to end extraction. If omitted, `slice`
* extracts to the end of the string.
* @return {String} All characters from specified start up to (but excluding)
* end.
*/
<span id='String-method-split'>/**
</span> * @method split
* Splits a `String` object into an array of strings by separating the string into substrings.
*
* The `split` method returns the new array.
*
* When found, `separator` is removed from the string and the substrings are returned in an array. If
* `separator` is omitted, the array contains one element consisting of the entire string.
*
* If `separator` is a regular expression that contains capturing parentheses, then each time separator
* is matched the results (including any undefined results) of the capturing parentheses are spliced
* into the output array. However, not all browsers support this capability.
*
* Note: When the string is empty, `split` returns an array containing one empty string, rather than an
* empty array.
*
* The following example defines a function that splits a string into an array of strings using the
* specified separator. After splitting the string, the function displays messages indicating the
* original string (before the split), the separator used, the number of elements in the array, and the
* individual array elements.
*
* function splitString(stringToSplit,separator)
* {
* var arrayOfStrings = stringToSplit.split(separator);
* print('The original string is: "' + stringToSplit + '"');
* print('The separator is: "' + separator + '"');
* print("The array has " + arrayOfStrings.length + " elements: ");
*
* for (var i=0; i < arrayOfStrings.length; i++)
* print(arrayOfStrings[i] + " / ");
* }
*
* var tempestString = "Oh brave new world that has such people in it.";
* var monthString = "Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec";
*
* var space = " ";
* var comma = ",";
*
* splitString(tempestString, space);
* splitString(tempestString);
* splitString(monthString, comma);
*
* This example produces the following output:
*
* The original string is: "Oh brave new world that has such people in it."
* The separator is: " "
* The array has 10 elements: Oh / brave / new / world / that / has / such / people / in / it. /
*
* The original string is: "Oh brave new world that has such people in it."
* The separator is: "undefined"
* The array has 1 elements: Oh brave new world that has such people in it. /
*
* The original string is: "Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec"
* The separator is: ","
* The array has 12 elements: Jan / Feb / Mar / Apr / May / Jun / Jul / Aug / Sep / Oct / Nov / Dec /
*
* In the following example, `split` looks for 0 or more spaces followed by a semicolon followed by 0
* or more spaces and, when found, removes the spaces from the string. nameList is the array returned
* as a result of split.
*
* var names = "Harry Trump ;Fred Barney; Helen Rigby ; Bill Abel ;Chris Hand ";
* print(names);
* var re = /\s*;\s*\/;
* var nameList = names.split(re);
* print(nameList);
*
* This prints two lines; the first line prints the original string, and the second line prints the
* resulting array.
*
* Harry Trump ;Fred Barney; Helen Rigby ; Bill Abel ;Chris Hand
* Harry Trump,Fred Barney,Helen Rigby,Bill Abel,Chris Hand
*
* In the following example, split looks for 0 or more spaces in a string and returns the first 3
* splits that it finds.
*
* var myString = "Hello World. How are you doing?";
* var splits = myString.split(" ", 3);
* print(splits);
*
* This script displays the following:
*
* Hello,World.,How
*
* If `separator` contains capturing parentheses, matched results are returned in the array.
*
* var myString = "Hello 1 word. Sentence number 2.";
* var splits = myString.split(/(\d)/);
* print(splits);
*
* This script displays the following:
*
* Hello ,1, word. Sentence number ,2, .
*
* @param {String} seperator Specifies the character to use for separating the string. The separator is treated as a string or a
* regular expression. If separator is omitted, the array returned contains one element consisting of the entire string.
* @param {Number} limit Integer specifying a limit on the number of splits to be found. The split method still splits on every
* match of separator, but it truncates the returned array to at most limit elements.
* @return {Array} Substrings are returned in an array.
*/
<span id='String-method-substr'>/**
</span> * @method substr
* Returns the characters in a string beginning at the specified location through the specified number
* of characters.
*
* `start` is a character index. The index of the first character is 0, and the index of the last
* character is 1 less than the length of the string. `substr` begins extracting characters at start
* and collects length characters (unless it reaches the end of the string first, in which case it will
* return fewer).
*
* If `start` is positive and is greater than or equal to the length of the string, `substr` returns an
* empty string.
*
* If `start` is negative, `substr` uses it as a character index from the end of the string. If start
* is negative and abs(start) is larger than the length of the string, `substr` uses 0 as the start
* index. Note: the described handling of negative values of the start argument is not supported by
* Microsoft JScript.
*
* If length is 0 or negative, `substr` returns an empty string. If length is omitted, `substr`
* extracts characters to the end of the string.
*
* Consider the following script:
*
* // assumes a print function is defined
* var str = "abcdefghij";
* print("(1,2): " + str.substr(1,2));
* print("(-3,2): " + str.substr(-3,2));
* print("(-3): " + str.substr(-3));
* print("(1): " + str.substr(1));
* print("(-20, 2): " + str.substr(-20,2));
* print("(20, 2): " + str.substr(20,2));
*
* This script displays:
*
* (1,2): bc
* (-3,2): hi
* (-3): hij
* (1): bcdefghij
* (-20, 2): ab
* (20, 2):
*
* @param {Number} start Location at which to begin extracting characters.
* @param {Number} length The number of characters to extract.
* @return {String} Modified string.
*/
<span id='String-method-substring'>/**
</span> * @method substring
* Returns the characters in a string between two indexes into the string.
*
* substring extracts characters from indexA up to but not including indexB. In particular:
* * If `indexA` equals `indexB`, `substring` returns an empty string.
* * If `indexB` is omitted, substring extracts characters to the end of the string.
* * If either argument is less than 0 or is `NaN`, it is treated as if it were 0.
* * If either argument is greater than `stringName.length`, it is treated as if it were
* `stringName.length`.
*
* If `indexA` is larger than `indexB`, then the effect of substring is as if the two arguments were
* swapped; for example, `str.substring(1, 0) == str.substring(0, 1)`.
*
* The following example uses substring to display characters from the string "Sencha":
*
* // assumes a print function is defined
* var anyString = "Sencha";
*
* // Displays "Sen"
* print(anyString.substring(0,3));
* print(anyString.substring(3,0));
*
* // Displays "cha"
* print(anyString.substring(3,6));
* print(anyString.substring(6,3));
*
* // Displays "Sencha"
* print(anyString.substring(0,6));
* print(anyString.substring(0,10));
*
* The following example replaces a substring within a string. It will replace both individual
* characters and `substrings`. The function call at the end of the example changes the string "Brave
* New World" into "Brave New Web".
*
* function replaceString(oldS, newS, fullS) {
* // Replaces oldS with newS in the string fullS
* for (var i = 0; i < fullS.length; i++) {
* if (fullS.substring(i, i + oldS.length) == oldS) {
* fullS = fullS.substring(0, i) + newS + fullS.substring(i + oldS.length,
* fullS.length);
* }
* }
* return fullS;
* }
*
* replaceString("World", "Web", "Brave New World");
*
* @param {Number} indexA An integer between 0 and one less than the length of the string.
* @param {Number} indexB (optional) An integer between 0 and the length of the string.
* @return {String} Returns the characters in a string between two indexes into the string.
*/
<span id='String-method-toLocaleLowerCase'>/**
</span> * @method toLocaleLowerCase
* The characters within a string are converted to lower case while respecting the current locale. For
* most languages, this will return the same as `toLowerCase`.
*
* The `toLocaleLowerCase` method returns the value of the string converted to lower case according to
* any locale-specific case mappings. `toLocaleLowerCase` does not affect the value of the string
* itself. In most cases, this will produce the same result as `toLowerCase()`, but for some locales,
* such as Turkish, whose case mappings do not follow the default case mappings in Unicode, there may
* be a different result.
*
* The following example displays the string "sencha":
*
* var upperText="sencha";
* document.write(upperText.toLocaleLowerCase());
*
* @return {String} Returns value of the string in lowercase.
*/
<span id='String-method-toLocaleUpperCase'>/**
</span> * @method toLocaleUpperCase
* The characters within a string are converted to upper case while respecting the current locale. For
* most languages, this will return the same as `toUpperCase`.
*
* The `toLocaleUpperCase` method returns the value of the string converted to upper case according to
* any locale-specific case mappings. `toLocaleUpperCase` does not affect the value of the string
* itself. In most cases, this will produce the same result as `toUpperCase()`, but for some locales,
* such as Turkish, whose case mappings do not follow the default case mappings in Unicode, there may
* be a different result.
*
* The following example displays the string "SENCHA":
*
* var lowerText="sencha";
* document.write(lowerText.toLocaleUpperCase());
*
* @return {String} Returns value of the string in uppercase.
*/
<span id='String-method-toLowerCase'>/**
</span> * @method toLowerCase
* Returns the calling string value converted to lower case.
*
* The `toLowerCase` method returns the value of the string converted to lowercase. `toLowerCase` does
* not affect the value of the string itself.
*
* The following example displays the lowercase string "sencha":
*
* var upperText="SENCHA";
* document.write(upperText.toLowerCase());
*
* @return {String} Returns value of the string in lowercase.
*/
<span id='String-method-toString'>/**
</span> * @method toString
* Returns a string representing the specified object. Overrides the `Object.toString` method.
*
* The `String` object overrides the `toString` method of the `Object` object; it does not inherit
* `Object.toString`. For `String` objects, the `toString` method returns a string representation of
* the object.
*
* The following example displays the string value of a String object:
*
* x = new String("Hello world");
* alert(x.toString()) // Displays "Hello world"
*
* @return {String} A string representation of the object.
*/
<span id='String-method-toUpperCase'>/**
</span> * @method toUpperCase
* Returns the calling string value converted to uppercase.
*
* The `toUpperCase` method returns the value of the string converted to uppercase. `toUpperCase` does
* not affect the value of the string itself.
*
* The following example displays the string "SENCHA":
* var lowerText="sencha";
* document.write(lowerText.toUpperCase());
*
* @return {String} Returns value of the string in uppercase.
*/
<span id='String-method-valueOf'>/**
</span> * @method valueOf
* Returns the primitive value of the specified object. Overrides the `Object.valueOf` method.
*
* The `valueOf` method of String returns the primitive value of a `String` object as a string data
* type. This value is equivalent to `String.toString`.
*
* This method is usually called internally by JavaScript and not explicitly in code.
*
* x = new String("Hello world");
* alert(x.valueOf()) // Displays "Hello world"
*
* @return {String} Returns value of string.
*/</pre>
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