Jquery.Form 异步提交表单实例

http://www.aqee.net/docs/jquery.form.plugin/jquery.form.plugin.html#getting-started

1. 在你的页面里写一个表单。一个普通的表单，不需要任何特殊的标记：

<form id="myForm" method="post" action="/Home/AjaxForm">
<div>
Name:<input id="username" name="username" type="text" />  
Password:<input id="password" name="password" type="text" />
<br />
<input type="submit" value="submit async" id="lnkSubmit" />
</div>
</form>

在没有Jquery.Form组件的时候，提交表单，页面会进入阻塞模式，等待服务器端的响应。

2. 引入jQuery和Form Plugin Javascript脚本文件并且添加几句简单的代码让页面在DOM加载完成后初始化表单：

<head> 
    <script type="text/javascript" src="path/to/jquery.js"></script> 
    <script type="text/javascript" src="path/to/form.js"></script> 
 
    <script type="text/javascript"> 
        // wait for the DOM to be loaded 
        $(document).ready(function() { 
            // bind 'myForm' and provide a simple callback function

            // 为myform绑定ajaxForm异步提交事件，并提供一个简单的回调函数。
            $('#myForm').ajaxForm(function() { 
                alert("Thank you for your comment!"); 
            }); 
        }); 
    </script> 
</head>

加上jquery.form组件后，提交表单时，页面不会再同步提交，而是由js做异步提交，因此提交后页面不会有刷新。

3. 加入能够与服务器端进行交互的回调函数。

$(document).ready(function () {

                  //options是一个ajaxForm的配置对象。

            var options = {
                //target: '#output1',   // target element(s) to be updated with server response 
                //beforeSubmit: showRequest,  // pre-submit callback 
                success: callBackFunc  // post-submit callback 

                // other available options: 
                //url:       url         // override for form's 'action' attribute 
                //type:      type        // 'get' or 'post', override for form's 'method' attribute 
                //dataType:  null        // 'xml', 'script', or 'json' (expected server response type) 
                //clearForm: true        // clear all form fields after successful submit 
                //resetForm: true        // reset the form after successful submit 

                // $.ajax options can be used here too, for example: 
                //timeout:   3000 
            };

            // bind form using 'ajaxForm' 
            $('#myForm').ajaxForm(options);
        });

        // responseText是服务端的响应值。statusText是页面

        // 提交状态值，success表示成功。
        function callBackFunc(responseText, statusText) {
            if (statusText == 'success') {
                alert(responseText);
            }

            else{

                 alert(“服务端错误！”);

             }
        }

如果返回的是json数据则回调函数可以这么写

function resultFunction(responseText,statusText) {
        if (statusText == 'success') {
            if (responseText.code == 1) {
                alert(responseText.message);
            } 
            else {
                alert('error occurs!');
            }
        }
        else {
            alert('服务器错误！');
        }
    }

服务端的代码如下

        [HttpPost]
        public ActionResult AjaxForm(FormCollection form)
        {
            string message = "Name:" + form["username"] + " PWD: "+form["password"]  ;
            //return Content(message);
            return Json(new { code = 1, message = message });
        }

4. 加入提交前的数据校验函数

为options对象添加 beforeSubmit属性

var options = {
                //target: '#output1',   // target element(s) to be updated with server response 
                beforeSubmit: checkData,  // pre-submit callback 
                success: callBackFunc  // post-submit callback 

                // other available options: 
                //url:       url         // override for form's 'action' attribute 
                //type:      type        // 'get' or 'post', override for form's 'method' attribute 
                //dataType:  null        // 'xml', 'script', or 'json' (expected server response type) 
                //clearForm: true        // clear all form fields after successful submit 
                //resetForm: true        // reset the form after successful submit 

                // $.ajax options can be used here too, for example: 
                //timeout:   3000 
            };

 // pre-submit callback 
        function checkData(formData, jqForm, options) {
            // formData is an array; here we use $.param to convert it to a string to display it 
            // but the form plugin does this for you automatically when it submits the data 
            //var queryString = $.param(formData);

            // jqForm is a jQuery object encapsulating the form element.  To access the 
            // DOM element for the form do this: 
            var formElement = jqForm[0]; 

            //alert('About to submit: \n\n' + queryString);

            // here we could return false to prevent the form from being submitted; 
            // returning anything other than false will allow the form submit to continue 
            //return true;
            if ($(formElement).find("#username").val() == "") {
                alert("please enter username!");
                return false;
            } else {
                return true;
            }
        }

验证用户名是否为空，是则提示输入，并取消表单提交。