js表单验证方法1

                        <form role="form" name="form">
                            <fieldset>
                                <div class="form-group">
                                    <input class="form-control" placeholder="Username" name="username" type="email" autofocus>
                                </div>
                                <div class="form-group">
                                    <input class="form-control" placeholder="Password" name="password" type="password" value="">
                                </div>
                                <div class="checkbox">
                                    <label>
                                        <input name="remember" type="checkbox" value="Remember Me">Remember Me
                                    </label>
                                </div>
                                <a href="javascript:void(0)" class="btn btn-lg btn-success btn-block" οnclick="checkData()">Login</a>
                            </fieldset>
                        </form>

1.js代码可以通过name获取input里面的值进行表单验证

function checkData(){
	alert(document.form.username.value);
}

(1)只要在form标签里面加上name属性
(2)通过value获取文本框中的值