/**
* 不加paste鼠标粘贴不起作用
* 不加input第一次粘贴的时候不变
* 加上input和focus可以兼容表情
* keydown兼容IE6下按键不放
*/
$('#email_pass').bind("keyup paste focus keydown",function(e) {
//(?=^.{8,}$)((?=.*\d)|(?=.*\W+))(?![.\n])(?=.*[A-Z])(?=.*[a-z]).*$ 强度密码正则（可选）
var strongRegex = new RegExp("^(?=.{8,})(?=.*[A-Z])(?=.*[a-z])(?=.*[0-9])(?=.*\\W).*$", "g");
var mediumRegex = new RegExp("^(?=.{7,})(((?=.*[A-Z])(?=.*[a-z]))|((?=.*[A-Z])(?=.*[0-9]))|((?=.*[a-z])(?=.*[0-9]))).*$", "g");
var enoughRegex = new RegExp("(?=.{6,}).*", "g");
if (false == enoughRegex.test($(this).val())) {
$('#strong').css('background-color','#FF6600');
$('#good').css('background-color','#FF6600');
$('#weak').css('background-color','#FF6600');
} else if (strongRegex.test($(this).val())) {
$('#strong').css('backgroundColor','green');
$('#good').css('backgroundColor','green');
$('#weak').css('background-color','green');
} else if (mediumRegex.test($(this).val())) {
$('#good').css('backgroundColor','green');
$('#weak').css('background-color','green');
$('#strong').css('background-color','#FF6600');
} else {
$('#weak').css('background-color','green');
$('#strong').css('background-color','#FF6600');
$('#good').css('background-color','#FF6600');
}
return true;
});
<input type="password" name="pass" id="email_pass" />
<span id="passstrength"></span>
