顯示密碼安全性強度

<div class="from-nav">
                        <div class="Mtitle"><span>密码:</span></div>
                        <div class="Mright"><input name="password" type="password" id="password" size="20" class="colorblue" onfocus="this.className='colorfocus';" onblur="this.className='colorblue';" onkeyup="return loadinputcontext(this);" /><span>不得少于6个字符</span>
                        </div>
    </div>
    <div class="from-nav">
                        <div class="Mtitle"><span>密码强度:</span></div>
                        <div class="Mright">
<script type="text/javascript">
        var PasswordStrength ={
            Level : ["极佳","一般","较弱","太短"],
            LevelValue : [15,10,5,0],//强度值
            Factor : [1,2,5],//字符加数,分别为字母，数字，其它
            KindFactor : [0,0,10,20],//密码含几种组成的加数 
            Regex : [/[a-zA-Z]/g,/\d/g,/[^a-zA-Z0-9]/g] //字符正则数字正则其它正则
            }
        PasswordStrength.StrengthValue = function(pwd)
        {
            var strengthValue = 0;
            var ComposedKind = 0;
            for(var i = 0 ; i < this.Regex.length;i++)
            {
                var chars = pwd.match(this.Regex[i]);
                if(chars != null)
                {
                    strengthValue += chars.length * this.Factor[i];
                    ComposedKind ++;
                }
            }
            strengthValue += this.KindFactor[ComposedKind];
            return strengthValue;
        } 
        PasswordStrength.StrengthLevel = function(pwd)
        {
            var value = this.StrengthValue(pwd);
            for(var i = 0 ; i < this.LevelValue.length ; i ++)
            {
                if(value >= this.LevelValue[i] )
                    return this.Level[i];
            }
        }
        function loadinputcontext(o)
        {
           var showmsg=PasswordStrength.StrengthLevel(o.value);
           switch(showmsg)
           {
              case "太短": showmsg+=" <img src='images/level/1.gif' width='88' height='11' />";break;
              case "较弱": showmsg+=" <img src='images/level/2.gif' width='88' height='11' />";break;
              case "一般": showmsg+=" <img src='images/level/3.gif' width='88' height='11' />";break;
              case "极佳": showmsg+=" <img src='images/level/4.gif' width='88' height='11' />";break;
           }
           document.getElementById('showmsg').innerHTML = showmsg;
        }
        function htmlEncode(source, display, tabs)
        {
            function special(source)
            {
                var result = '';
                for (var i = 0; i < source.length; i++)
                {
                    var c = source.charAt(i);
                    if (c < ' ' || c > '~')
                    {
                        c = '&#' + c.charCodeAt() + ';';
                    }
                    result += c;
                }
                return result;
            }
            function format(source)
            {
                // Use only integer part of tabs, and default to 4
                tabs = (tabs >= 0) ? Math.floor(tabs) : 4;
                // split along line breaks
                var lines = source.split(/\r\n|\r|\n/);
                // expand tabs
                for (var i = 0; i < lines.length; i++)
                {
                    var line = lines[i];
                    var newLine = '';
                    for (var p = 0; p < line.length; p++)
                    {
                        var c = line.charAt(p);
                        if (c === '\t')
                        {
                            var spaces = tabs - (newLine.length % tabs);
                            for (var s = 0; s < spaces; s++)
                            {
                                newLine += ' ';
                            }
                        }
                        else
                        {
                            newLine += c;
                        }
                    }
                    // If a line starts or ends with a space, it evaporates in html
                    // unless it's an nbsp.
                    newLine = newLine.replace(/(^ )|( $)/g, '&nbsp;');
                    lines[i] = newLine;
                }
                // re-join lines
                var result = lines.join('<br />');
                // break up contiguous blocks of spaces with non-breaking spaces
                result = result.replace(/  /g, ' &nbsp;');
                // tada!
                return result;
            }
            var result = source;
            // ampersands (&)
            result = result.replace(/\&/g,'&amp;');
            // less-thans (<)
            result = result.replace(/\</g,'&lt;');
            // greater-thans (>)
            result = result.replace(/\>/g,'&gt;');
            if (display)
            {
                // format for display
                result = format(result);
            }
            else
            {
                // Replace quotes if it isn't for display,
                // since it's probably going in an html attribute.
                result = result.replace(new RegExp('"','g'), '&quot;');
            }
            // special characters
            result = special(result);
            // tada!
            return result;
        }
        var profile_username_toolong = '对不起，您的用户名超过 20 个字符，请输入一个较短的用户名。';
        var profile_username_tooshort = '对不起，您输入的用户名小于3个字符, 请输入一个较长的用户名。';
        var profile_username_pass = "可用";
        function checkusername(username)
        {
            var unlen = username.replace(/[^\x00-\xff]/g, "**").length;
            if(unlen < 3 || unlen > 20) {
                document.getElementById("checkresult").innerHTML = "<font color='#009900'>" + (unlen < 3 ? profile_username_tooshort : profile_username_toolong) + "</font>";
                return;
            }
            ajaxRead("tools/ajax.aspx?t=checkusername&username=" + escape(username), "showcheckresult(obj,'" + username + "');");
        }
        function showcheckresult(obj, username)
        {
            var res = obj.getElementsByTagName('result');
            var resContainer = document.getElementById("checkresult");
            var result = "";
            if (res[0] != null && res[0] != undefined)
            {
                if (res[0].childNodes.length > 1) {
                    result = res[0].childNodes[1].nodeValue;
                } else {
                    result = res[0].firstChild.nodeValue;            
                }
            }
            if (result == "1")
            {
                resContainer.innerHTML = "<font color='#009900'>对不起，您输入的用户名 \"" + htmlEncode(username, true, 4) + "\" 已经被他人使用或被禁用，请选择其他名字后再试。</font>";
            }
            else
            {
                resContainer.innerHTML = profile_username_pass;
            }
        }
</script>
<script type="text/javascript" src="templates/default/ajax.js"></script>
             <span id="showmsg"></span>
                </div>
    </div>