js 验证密码强度的例子

用js验证密码的强度，代码如下：
1，js代码部分

<script>
/**
* 检测密码的强度
* by www.jb200.com
*/
function isSecurity(v){
if (v.length < 3){iss.reset();return;}
var lv = -1;
if (v.match(/[a-z]/ig)){lv++;}
if (v.match(/[0-9]/ig)){lv++;}
if (v.match(/(.[^a-z0-9])/ig)){lv++;}
if (v.length < 6 && lv > 0){lv--;}
iss.reset();
switch(lv)
{
case 0:
iss.level0();
break;
case 1:
iss.level1();
break;
case 2:
iss.level2();
break;
default:
iss.reset();
}
}
var iss = {
color:["CC0000","FFCC33","66CC00","CCCCCC"],
text:["弱","中","强"],
    width:["50","100","150","10"],
reset:function(){
$("B").style.backgroundColor = iss.color[3];
      $("B").style.width = iss.width[3];
$("A").innerHTML = "验证试中";

},
level0:function(){
$("B").style.backgroundColor = iss.color[0];
      $("B").style.width = iss.width[0];
      $("A").innerHTML = "较弱"; 
},
level1:function(){
$("B").style.backgroundColor = iss.color[1];
      $("B").style.width = iss.width[1];
$("A").innerHTML = "中";
},
level2:function(){
$("B").style.backgroundColor = iss.color[2];
      $("B").style.width = iss.width[2];
$("A").innerHTML = "高强";

}
}
var $ = function(v){return document.getElementById(v);}
</script>

2，html部分

<input type=password name=password size=25 maxlength=20 onkeyup="isSecurity(this.value);">
<font class=red id=A>密码强度</font>
<table  height="8" border="1" align="left" cellpadding="0" cellspacing="0" bordercolor="#EEEEEE" style="border-collapse:collapse;">
<tr>
<td bgcolor="#EEEEEE" width="1" align="center" valign="middle" id="B"></td>
</table>