1.Между head /head страницы регистрации :

Code
<script src="http://jqueryjs.googlecode.com/files/jquery-1.2.6.min.js" type="text/javascript"></script>

<script type="text/javascript">
$.fn.passwordStrength = function( options ){
return this.each(function(){
var that = this;that.opts = {};
that.opts = $.extend({}, $.fn.passwordStrength.defaults, options);

that.div = $(that.opts.targetDiv);
that.defaultClass = that.div.attr("class");

that.percents = (that.opts.classes.length) ? 100 / that.opts.classes.length : 100;

v = $(this)
.keyup(function(){
if( typeof el == "undefined" )
this.el = $(this);
var s = getPasswordStrength (this.value);
var p = this.percents;
var t = Math.floor( s / p );

if( 100 <= s )
t = this.opts.classes.length - 1;

this.div
.removeAttr("class")
.addClass( this.defaultClass )
.addClass( this.opts.classes[ t ] );

})
.after("")
.next()
.click(function(){
$(this).prev().val ( randomPassword() ).trigger("keyup");
return false;
});
});

function getPasswordStrength(H){
var D=(H.length);
if(D>5){
D=5
}
var F=H.replace(/[0-9]/g,"");
var G=(H.length-F.length);
if(G>3){G=3}
var A=H.replace(/\W/g,"");
var C=(H.length-A.length);
if(C>3){C=3}
var B=H.replace(/[A-Z]/g,"");
var I=(H.length-B.length);
if(I>3){I=3}
var E=((D*10)-20)+(G*10)+(C*15)+(I*10);
if(E<0){E=0}
if(E>100){E=100}
return E
}

function randomPassword() {
var chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$_+";
var size = 10;
var i = 1;
var ret = ""
while ( i <= size ) {
$max = chars.length-1;
$num = Math.floor(Math.random()*$max);
$temp = chars.substr($num, 1);
ret += $temp;
i++;
}
return ret;
}

};

$.fn.passwordStrength.defaults = {
classes : Array("is10","is20","is30","is40","is50","is60","is70","is80","is90","is100"),
targetDiv : "#passwordStrengthDiv",
cache : {}
}
$(document)
.ready(function(){
$("input[name="password"]").passwordStrength();
});
</script>

CSS

Code
.is0{background:url("http://s58.radikal.ru/i161/0902/1e/827549f7747a.png") no-repeat 0 0;width:138px;height:7px;}
.is10{background-position:0 -7px;}

Автор: 123

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