<link href="../css/screen.css" rel="stylesheet" />

<script type="text/javascript" src="../js/jquery.js"></script>

<script type="text/javascript" src="../js/jquery.validate.js"></script>

<script type="text/javascript" src="../js/messages_zh.js"></script>

<script type="text/javascript" src="../js/index.js"></script>

    <form class="cmxform" id="commentForm" method="get" action="">

            <p>

                <label for="cname">Name(必需, 最小两个字母)</label>

                <input id="cname" name="name" minlength="2" type="text" required />

            </p>

            <p>

                <label for="cemail">E-Mail (必需)</label>

                <input id="cemail" type="email" name="email" required>

            </p>

            <p>

                <label for="curl">URL (可选)</label>

                <input id="curl" type="url" name="url">

            </p>

            <p>

                <label for="ccomment">备注 (必需)</label>

                <textarea id="ccomment" name="comment" required></textarea>

            </p>

            <p>

                <input class="submit" type="submit" value="Submit">

            </p>

    </form>

$(function() {

    $("#commentForm").validate();

});

$.validator.setDefaults({

    submitHandler: function() {

      alert("提交事件!");

    }

});

<form class="cmxform" id="signupForm" method="get" action="">

        <p>

            <label for="firstname">名字</label> <input id="firstname"

                name="firstname" type="text">

        </p>

        <p>

            <label for="lastname">姓氏</label> <input id="lastname" name="lastname"

                type="text">

        </p>

        <p>

            <label for="username">用户名</label> <input id="username"

                name="username" type="text">

        </p>

        <p>

            <label for="password">密码</label> <input id="password" name="password"

                type="password">

        </p>

        <p>

            <label for="confirm_password">验证密码</label> <input

                id="confirm_password" name="confirm_password" type="password">

        </p>

        <p>

            <label for="email">Email</label> <input id="email" name="email"

                type="email">

        </p>

        <p>

            <label for="agree">请同意我们的声明</label> <input type="checkbox"

                class="checkbox" id="agree" name="agree">

        </p>

        <p>

            <input class="submit" type="submit" value="提交">

        </p>

        </fieldset>

    </form>

$(function() {

    $("#signupForm").validate({

        rules: {

            firstname: "required",

            lastname: "required",

            username: {

                required: true,

                minlength: 2

            },

            password: {

                required: true,

                minlength: 5

            },

            confirm_password: {

                required: true,

                minlength: 5,

                equalTo: "#password"//校验两次密码相同

            },

            email: {

                required: true,

                email: true

            },

            topic: {

                required: "#newsletter:checked",

                minlength: 2

            },

            agree: "required"

        },

        messages: {

            firstname: "请输入您的名字",

            lastname: "请输入您的姓氏",

            username: {

                required: "请输入用户名",

                minlength: "用户名必需由两个字母组成"

            },

            password: {

                required: "请输入密码",

                minlength: "密码长度不能小于 5 个字母"

            },

            confirm_password: {

                required: "请输入密码",

                minlength: "密码长度不能小于 5 个字母",

                equalTo: "两次密码输入不一致"

            },

            email: "请输入一个正确的邮箱",

            agree: "请接受我们的声明"

        }

    })

});

$.validator.setDefaults({

    submitHandler: function() {

        alert("提交事件!");

    }

});