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。
js代码
<script type="text/javascript">
String.prototype.replaceAll = function(reallyDo, replaceWith, ignoreCase) {
if (!RegExp.prototype.isPrototypeOf(reallyDo)) {
return this.replace(new RegExp(reallyDo, (ignoreCase ? "gi": "g")), replaceWith);
} else {
return this.replace(reallyDo, replaceWith);
}
}
</script>
