第一次发现JavaScript中replace() 方法如果直接用str.replace("-","!") 只会替换第一个匹配的字符. 而str.replace(/\-/g,"!")则可以全部替换掉匹配的字符(g为全局标志)。
replace() The replace() method returns the string that results when you replace text matching its first argument (a regular expression) with the text of the second argument (a string). If the g (global) flag is not set in the regular expression declaration, this method replaces only the first occurrence of the pattern. For example,
var s = "Hello. Regexps are fun." ;s = s.replace(/\./, "!" ); // replace first period with an exclamation pointalert(s);
produces the string “Hello! Regexps are fun.” Including the g flag will cause the interpreter to perform a global replace, finding and replacing every matching substring. For example,
var s = "Hello. Regexps are fun." ;s = s.replace(/\./g, "!" ); // replace all periods with exclamation pointsalert(s);
yields this result: “Hello! Regexps are fun!”
所以可以用以下几种方式.： string.replace(/reallyDo/g, replaceWith); string.replace(new RegExp(reallyDo, 'g'), replaceWith);
string：字符串表达式包含要替代的子字符串。 reallyDo：被搜索的子字符串。 replaceWith：用于替换的子字符串。
1.<script type="text/javascript">
2.String.prototype.replaceAll = function(reallyDo, replaceWith, ignoreCase) {
3. if (!RegExp.prototype.isPrototypeOf(reallyDo)) {
4. return this.replace(new RegExp(reallyDo, (ignoreCase ? "gi": "g")), replaceWith);
5. } else {
6. return this.replace(reallyDo, replaceWith);
7. }
8.}
9.</script>