ExtJs是一套非常不错的javascript UI库(第一次接触ExtJs的，可到官方网站http://www.extjs.com/deploy/dev/examples/samples.html看下示例。相信不少人会心动的)，不仅组件丰富，效果漂亮，而且ExtJs集成的Ajax功能可以方便的与.Net的WCF进行交互.
这里我们将演示ExtJs的FormPanel从WCF加载数据，以及如何提交数据到WCF服务端
1.首先来定义一个用于传输信息的Class（实际开发中，可以是Linq to Sql的Class或任何可序列化的实体类）
[DataContract]
public class MyData
{
[DataMember]
public string id;
[DataMember]
public string text;
}非常简单，MyData中仅定义了二个成员id,text，加上[DataContract]与[DataMember]表明该类可以序列化
2.再定义几个用于跟ExtJs交互的方法(初次接触Ajax与WCF交互的同志，建议参考一下老张的"Ajax与WCF交互-WCF之美。
[ServiceContract(Namespace = "")]
[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class MyService
{
[OperationContract]
[WebInvoke(ResponseFormat = WebMessageFormat.Json, Method = "*", UriTemplate = "GetMyData")]
public MyData GetMyData()
{
System.Threading.Thread.Sleep(1000);
MyData _Node = new MyData() { id = "1", text = "test text" };
return _Node;
}
/// <summary>
/// RESTFul WCF用于Get方式取得ExtJs提交的数据(Json)
/// </summary>
/// <param name="id"></param>
/// <param name="text"></param>
/// <returns></returns>
[OperationContract]
[WebInvoke(Method = "*", ResponseFormat = WebMessageFormat.Json, UriTemplate = "SaveMyData?id={id}&text={text}")]
public MyData SaveMyData(string id,string text)
{
System.Threading.Thread.Sleep(1000);
MyData _Node = new MyData() { id = id, text = text };
return _Node;
}
/// <summary>
/// Post方法处理ExtJs提交的数据(Json格式)
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
[OperationContract]
[WebInvoke(Method = "*", ResponseFormat = WebMessageFormat.Json, UriTemplate = "SaveMyData2")]
public MyData SaveMyData2(Stream input)
{
string s = "";
using (StreamReader sr = new StreamReader(input))
{
s = sr.ReadToEnd();
}
NameValueCollection qs = HttpUtility.ParseQueryString(s);
string id = qs["id"];
string text = qs["text"];
System.Threading.Thread.Sleep(1000);
MyData _Node = new MyData() { id = id, text = text };
return _Node;
}
}这里定义了三个方法，GetMyData用来让ExtJs获取WCF端的数据，SaveMyData,SaveMyData2用来保存ExtJs提交过来的数据，区别是SaveMyData用于Get方法,SaveMyData2用于Post方法
需要说明的是[WebInvoke(Method = "*", ResponseFormat = WebMessageFormat.Json, UriTemplate = "SaveMyData?id={id}&text={text}")]这一行，这里标明该方法可用Get/Post来处理数据，输出格式是Json字符串，UriTemplate表示该方法支持RESTFul风格，可用/MyService.svc?id=xxx&text=xxx来访问(关于RESTFul WCF，可参见雨痕的文章http://www.rainsts.net/article.asp?id=651 [RESTful WCF])
3.ExtJs前端页面
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="FormTest.aspx.cs" Inherits="Ajax_WCF.FormTest" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title></title>
<link rel="stylesheet" type="text/css" href="js/ext2.2/resources/css/ext-all.css" />
<script type="text/javascript" src="js/ext2.2/adapter/ext/ext-base.js"></script>
<script type="text/javascript" src="js/ext2.2/ext-all.js"></script>
<style>
*{font-size:9pt;line-height:120%;}
</style>
</head>
<body>
<script type="text/javascript">
Ext.onReady(function() {
var form = new Ext.FormPanel({
title: "loadData from Server",
autoHeight: true,
labelAlign: "top",
width: 400,
frame: true,
renderTo: Ext.getBody(),
defaults: { labelWidth: 80, anchor: "95%" },
items: [{
xtype: "textfield",
fieldLabel: "id",
name: "id",
anchor: "90%"
}, {
xtype: "textfield",
fieldLabel: "text",
name: "text",
anchor: "90%"
}],
buttons: [{ text: "加载数据", handler: function() {
//form的load方法总是不成功，无奈只能用Ext.Ajax对象来处理
var loading = Ext.get("loading");
loading.dom.innerHTML = "正在加载。。。";
Ext.Ajax.request({
url: "MyService.svc/GetMyData", //服务器端地址
success: function(request) {
var data = Ext.util.JSON.decode(request.responseText); //将服务端wcf的返回值，格式化为Json对象
form.getForm().setValues(data); //更新form
loading.dom.innerHTML = "";
},
failure: function() {
alert("failure!");
}
});
}
}, {
text: "保存(Get方法)", handler: function() {
var loading = Ext.get("loading");
loading.dom.innerHTML = "正在保存。。。";
Ext.Ajax.request({
url: "MyService.svc/SaveMyData",
method: "GET",
params: { id: "001", text: "Get方法提交的数据" }, //这里为了演示用，随便给出几个值，实际开发时，可将测试值改为用Ext.get("id").dom.value之类
，如果提交成功，将从服务器返回处理结果
success: function(request) {
var data = request.responseText;
loading.dom.innerHTML = "";
alert(data);
},
failure: function() {
alert("failure!");
}
});
}
}, {
text: "保存(Post方法)", handler: function() {
var loading = Ext.get("loading");
loading.dom.innerHTML = "正在保存。。。";
Ext.Ajax.request({
url: "MyService.svc/SaveMyData2",
method: "POST",//注意这里
params: { id: "002", text: "Post方法提交的数据" },
success: function(request) {
var data = request.responseText;
loading.dom.innerHTML = "";
alert(data);
},
failure: function() {
alert("failure!");
}
});
}
}]
});
});
</script>
<div id="loading" style="color:red"> </div>
</body>
</html>这里利用ExtJs的Ajax对象完成与WCF的交互(初次接触ExtJs Ajax的，可参见ExtJs学习笔记(5)_Ajax示例http://www.cnblogs.com/yjmyzz/archive/2008/08/30/1279918.html)，相当简单!
最近学习了ExtJs和WCF后，个人强力推荐.net3.x时代web开发的绝佳组合: ExtJs(前端) + WCF(web服务层) + Linq To Sql(DAL，以后可能会换成Ado.Net Entity FrameWork)，用起来简直是一种享受，目前用ExtJs的人似乎还不多。