PHP jQuery表单,带验证具体实现方法

<div id="container"> 
        <?if( isset($_post['send']) && (!validatename($_post['name']) || !validateemail($_post['email']) || !validatepasswords($_post['pass1'], $_post['pass2']) || !validatemessage($_post['message']) ) ):?> 
                <div id="error"> 
                    <ul> 
                        <?if(!validatename($_post['name'])):?> 
                            <li><strong>invalid name:</strong> we want names with more than 3 letters!</li> 
                        <?endif?> 
                        <?if(!validateemail($_post['email'])):?> 
                            <li><strong>invalid e-mail:</strong> stop cowboy! type a valid e-mail please :p</li> 
                        <?endif?> 
                        <?if(!validatepasswords($_post['pass1'], $_post['pass2'])):?> 
                            <li><strong>passwords are invalid:</strong> passwords doesn't match or are invalid!</li> 
                        <?endif?> 
                        <?if(!validatemessage($_post['message'])):?> 
                            <li><strong>ivalid message:</strong> type a message with at least with 10 letters</li> 
                        <?endif?> 
                    </ul> 
                </div> 
            <?elseif(isset($_post['send'])):?> 
                <div id="error" class="valid"> 
                    <ul> 
                        <li><strong>congratulations!</strong> all fields are ok ;)</li> 
                    </ul> 
                </div> 
        <?endif?> 

        <form method="post" id="customform" action=""> 
            <div> 
                <label for="name">name</label> 
                <input id="name" name="name" type="text" /> 
                <span id="nameinfo">what's your name?</span> 
            </div> 
            <div> 
                <label for="email">e-mail</label> 
                <input id="email" name="email" type="text" /> 
                <span id="emailinfo">valid e-mail please, you will need it to log in!</span> 
            </div> 
            <div> 
                <label for="pass1">password</label> 
                <input id="pass1" name="pass1" type="password" /> 
                <span id="pass1info">at least 5 characters: letters, numbers and '_'</span> 
            </div> 
            <div> 
                <label for="pass2">confirm password</label> 
                <input id="pass2" name="pass2" type="password" /> 
                <span id="pass2info">confirm password</span> 
            </div> 
            <div> 
                <label for="message">message</label> 
                <textarea id="message" name="message" cols="" rows=""></textarea> 
            </div> 
            <div> 
                <input id="send" name="send" type="submit" value="send" /> 
            </div> 
        </form> 
    </div> 

<?php 
    function validatename($name){ 
        //if it's not valid 
        if(strlen($name) < 4) 
            return false; 
        //if it's valid 
        else 
            return true; 
    } 
    function validateemail($email){ 
        return ereg("^[a-za-z0-9]+[a-za-z0-9_-]+@[a-za-z0-9]+[a-za-z0-9.-]+[a-za-z0-9]+.[a-z]{2,4}$", $email); 
    } 
    function validatepasswords($pass1, $pass2) { 
        //if doesn't match 
        if(strpos($pass1, ' ') !== false)
            return false;
        //if are valid
        return $pass1 == $pass2 && strlen($pass1) > 5;
    }
    function validatemessage($message){
        //if it's not valid 
        if(strlen($message) < 10) 
            return false; 
        //if it's valid 
        else 
            return true; 
    } 
?>