密码强度检测

 <html>
<head>
<title>密码强度检测</title>
<script type="text/javascript">
 function chkpwd(obj){
  var t=obj.value;
  var id=getResult(t);
 
  //定义对应的消息提示
  var msg=new Array(4);
  msg[0]="密码过短。";
  msg[1]="密码强度差。";
  msg[2]="密码强度良好。";
  msg[3]="密码强度高。";
 
  var sty=new Array(4);
  sty[0]=-45;
  sty[1]=-30;
  sty[2]=-15;
  sty[3]=0;
 
  var col = new Array(4);
  col[0] = "gray";
  col[1] = "#50AEDD";
  col[2] = "#FF8213";
  col[3] = "green";
 
  //设置显示效果
  var bImg="http://images.cnblogs.com/cnblogs_com/tq0855n/pwdlen_dSIPeEGQWxfO.gif" //一张显示用的图片
  var sWidth=300;
  var sHeight=15;
  var Bobj=document.getElementById("chkResult");

  Bobj.style.fontSize="12px";
  Bobj.style.color=col[id];
  Bobj.style.width=sWidth + "px";
  Bobj.style.height=sHeight + "px";
  Bobj.style.lineHeight=sHeight + "px";
  Bobj.style.background="url(" + bImg + ") no-repeat left " + sty[id] + "px";
  Bobj.style.textIndent="20px";
  Bobj.innerHTML="检测提示：" + msg[id];
 }
 
 //定义检测函数,返回0/1/2/3分别代表无效/差/一般/强
 function getResult(s){
  if(s.length < 4){
   return 0;
  }
  var ls = 0;
  if (s.match(/[a-z]/ig)){
   ls++;
  }
  if (s.match(/[0-9]/ig)){
   ls++;
  }
   if (s.match(/(.[^a-z0-9])/ig)){
   ls++;
  }
  if (s.length < 6 && ls > 0){
   ls--;
  }
  return ls
 }
</script>
</head>
<body>
<form name="form1">
 <label for="pwd">用户密码</label>
 <input type="password" name="pwd" onkeyup="chkpwd(this)" />
 <div id="chkResult"></div>
</form>
</body>
</html>