要在js中进行字符或字符串替换我们可以用到replace()方法用于在字符串中用一些字符替换另一些字符，或替换一个与正则表达式匹配的子串。
stringObject.replace(regexp/substr,replacement)
利用replace正则表达式替换
<html>
<script language="JavaScript1.2">
<!--
var myString = new String("This is a test");var myRegExp = /is/g;
var newString = myString.replace(myRegExp, "test www.111cn.net ");
document.write('Notice the last name in the original string, ' + myString);
document.write(', was replaced and is now '+ newString);
document.close();
-->
</script>
</html>
也可以直接用replace进行替换
<html>
<head>
<title>Using the replace() method of the String object</title>
<script type="text/网页特效" language="javascript">
<!-- //
var originalString = "A ab abc abcd";
var replacedString = "a";
var replacementString = "z";var newString = originalString.replace(replacedString, replacementString);
document.write("<h3>" + newString + "</h3");
// -->
</script>
</head>
<body></body>
</html>
对于中文我们最好用正则哦。