javascript的 replace() 方法的使用讲解

String.prototype.replace()


The replace() method returns a new string with some or all matches of a pattern replaced by a replacement.
The pattern can be a string or a RegExp, and the replacement can be a string or a function to be called for each match.
语法:
  str
.replace(regexp|substr, newSubStr|function[, flags])

Parameters

regexp (pattern)
RegExp object or literal. The match is replaced by the return value of parameter #2.
substr (pattern)
String that is to be replaced by newSubStr. It is treated as a verbatim string and is notinterpreted as a regular expression.
newSubStr (replacement)
The String that replaces the substring received from parameter #1. A number of special replacement patterns are supported; see the "Specifying a string as a parameter" section below.
function (replacement)
A function to be invoked to create the new substring (to put in place of the substring received from parameter #1). The arguments supplied to this function are described in the "Specifying a function as a parameter" section below.
例子:
例1:
var str = 'Twas the night before Xmas...';
var newstr = str.replace(/xmas/i, 'Christmas');
console.log(newstr); // Twas the night before Christmas...

例2:

var re = /apples/gi;
var str = 'Apples are round, and apples are juicy.';
var newstr = str.replace(re, 'oranges');
console.log(newstr); // oranges are round, and oranges are juicy.

例3:

var re = /(\w+)\s(\w+)/;
var str = 'John Smith';
var newstr = str.replace(re, '$2, $1');
console.log(newstr); // Smith, Joh

例4:

function styleHyphenFormat(propertyName) {
function upperToHyphenLower(match) {
return '-' + match.toLowerCase();
}
return propertyName.replace(/[A-Z]/g, upperToHyphenLower);
}

例5:

function replacer(match, p1, p2, p3, offset, string) {
// p1 is nondigits, p2 digits, and p3 non-alphanumerics
console.log(arguments);
return [p1, p2, p3].join(' - ');
}
var newString = 'abc12345#$*%aaa'.replace(/([^\d]*)(\d*)([^\w]*)/, replacer);

  

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