<html>
<head>
<script type="text/javascript">
//创建
var str = "aaafga";
var str1 = new String("aa");
var str2= String("aaasdrf");
//属性length
alert(str.length);
//方法charAt()
alert(str2.charAt(3));//s
//方法concat(str1,str2...）
alert(str.concat("dfa","55454"));
//方法indexOf
alert(str.indexOf("a",1));//1
// 方法replace（）;
alert(str.replace("a","k"));//kaafga
//方法 split（）;
var st = "1-2-3-5-4-1-2";
var v = st.split("-");
alert(v.length);//7
alert(v[0]);//1
//
</script>
</head>
<body>
this is my file
</body>
</html>