Flex与服务器交互之三（使用WebService组件同服务器WebService通讯） .

由于Flex只是一种客户端技术其本身并不能直接同数据库交互，在实际的应用开发过程中Flex提供了如URLRequest、HTTPService、RemoteObject、WebService等类以实现同服务器的通讯和数据交互，下面做一些介绍和实例解析:
   1、使用WebService组件同服务器交互
      WSDL描述以供Flex WebService解析调用相关接口信息(如图)：

     使用过程中在程序中添加一个WebService组件，设置WSDL属性为WebService的WSDL地址 调用<mx:operation>节点中定义的方法，设置result和fault事件函数接收ResultEvent和FaultEvent对象获取返回数据或捕获错误
      WebService组件官方帮助文档http://livedocs.adobe.com/flex/3/html/help.html?content=data_access_2.html
      WebService组件相关属性和事件:http://livedocs.adobe.com/flex/3/langref/mx/rpc/soap/mxml/WebService.html

     <mx:WebService
  Properties
   concurrency="multiple|single|last"
   destination="No default."
   id="No default."
   serviceName="No default."
   showBusyCursor="false|true"
   makeObjectsBindable="false|true"
   useProxy="false|true"
   wsdl="No default."               //请求的WSDL地址
   Events
 fault="No default."      //请求发生错误时触发的事件(通常在下面<operation>具体的方法中再具体定义)
 result="No default."      //请求完成后触发的事件以处理返回结果
 />

<mx:WebService Properties concurrency="multiple|single|last" destination="No default." id="No default." serviceName="No default." showBusyCursor="false|true" makeObjectsBindable="false|true" useProxy="false|true" wsdl="No default." //请求的WSDL地址 Events fault="No default." //请求发生错误时触发的事件(通常在下面<operation>具体的方法中再具体定义) result="No default." //请求完成后触发的事件以处理返回结果 /> 
  WebService调用方法节点属性和事件（可包含多个）

 <mx:operation
  Properties
   concurrency="multiple|single|last"
   name=No default, required.    //WebService方法名 必填
   resultFormat="object|xml|e4x"
   makeObjectsBindable="false|true"

  Events
 fault="No default."      //请求发生错误时触发的事件
 result="No default."      //请求完成后触发的事件以处理返回结果
 />

<mx:operation Properties concurrency="multiple|single|last" name=No default, required. //WebService方法名 必填 resultFormat="object|xml|e4x" makeObjectsBindable="false|true" Events fault="No default." //请求发生错误时触发的事件 result="No default." //请求完成后触发的事件以处理返回结果 />

 

   2、应用示例:（调用WebService 根据用户输入的ID 查询返回XML中用户详细信息）：
   服务器端WebService定义:
   

[WebService(Namespace = "http://csdn.richardjun.net/")]
   [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    [System.ComponentModel.ToolboxItem(false)]
    // To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.
    // [System.Web.Script.Services.ScriptService]
    public class SearchUserService : System.Web.Services.WebService
   {

       [WebMethod]
        public String SearchUserName(String useID)
       {
            XElement element = XElement.Load(Server.MapPath( @"/FlexService/Test.XML"));
            IEnumerable<XElement> uses = from v in element.Elements().ToList()
                                         where (String)v.Attribute("id") == useID
                                        select v;
            if (uses != null && uses.Count() > 0)
                return uses.First().ToString();
            else
                return String.Empty;
       }
   }

[WebService(Namespace = "http://csdn.richardjun.net/")] [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)] [System.ComponentModel.ToolboxItem(false)] // To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line. // [System.Web.Script.Services.ScriptService] public class SearchUserService : System.Web.Services.WebService { [WebMethod] public String SearchUserName(String useID) { XElement element = XElement.Load(Server.MapPath( @"/FlexService/Test.XML")); IEnumerable<XElement> uses = from v in element.Elements().ToList() where (String)v.Attribute("id") == useID select v; if (uses != null && uses.Count() > 0) return uses.First().ToString(); else return String.Empty; } }    

 

服务器端用户详细信息Test.XML文件:
 

<?xml version="1.0" encoding="utf-8" ?>
  <root xmlns="http:=//www.byd.com/ChartData/XML">
    <User id="0">
      <Name>宋江</Name>
      <NikeName>天魁星</NikeName>
      <Position>梁山泊寨主</Position>
      <Weapon>锟吾剑</Weapon>
    </User>
    <User id="1">
      <Name>卢俊义</Name>
      <NikeName>天罡星</NikeName>
      <Position>梁山泊副寨主</Position>
      <Weapon>枪、棒</Weapon>
    </User>
    <User id="2">
      <Name>吴用</Name>
      <NikeName>天机星</NikeName>
      <Position>梁山泊军师</Position>
      <Weapon>铜链</Weapon>
    </User>
    <User id="3">
      <Name>公孙胜</Name>
      <NikeName>天闲星</NikeName>
      <Position>梁山泊副军师</Position>
      <Weapon>松纹古定剑</Weapon>
    </User>
    <User id="4">
      <Name>大刀关胜</Name>
      <NikeName>天勇星</NikeName>
      <Position>梁山泊马军五虎大将之首</Position>
      <Weapon>青龙偃月刀</Weapon>
    </User>
    <User id="5">
      <Name>林冲</Name>
      <NikeName>天雄星豹子头</NikeName>
      <Position>梁山泊马军五虎大将之二</Position>
      <Weapon>丈八蛇矛</Weapon>
  </User>
  </root>

<?xml version="1.0" encoding="utf-8" ?> <root xmlns="http:=//www.byd.com/ChartData/XML"> <User id="0"> <Name>宋江</Name> <NikeName>天魁星</NikeName> <Position>梁山泊寨主</Position> <Weapon>锟吾剑</Weapon> </User> <User id="1"> <Name>卢俊义</Name> <NikeName>天罡星</NikeName> <Position>梁山泊副寨主</Position> <Weapon>枪、棒</Weapon> </User> <User id="2"> <Name>吴用</Name> <NikeName>天机星</NikeName> <Position>梁山泊军师</Position> <Weapon>铜链</Weapon> </User> <User id="3"> <Name>公孙胜</Name> <NikeName>天闲星</NikeName> <Position>梁山泊副军师</Position> <Weapon>松纹古定剑</Weapon> </User> <User id="4"> <Name>大刀关胜</Name> <NikeName>天勇星</NikeName> <Position>梁山泊马军五虎大将之首</Position> <Weapon>青龙偃月刀</Weapon> </User> <User id="5"> <Name>林冲</Name> <NikeName>天雄星豹子头</NikeName> <Position>梁山泊马军五虎大将之二</Position> <Weapon>丈八蛇矛</Weapon> </User> </root>

 

Felx代码：
    

<mx:Canvas x="10" y="218" width="393" height="200" backgroundColor="#84DACF">
   <mx:Label x="4" y="10" text="UserID:"/>
   <mx:Label x="60" y="83" width="160" id="labName" color="#C52167" fontSize="17"/>
   <mx:Label x="60" y="109" width="160" id="labPosition" color="#C52167" fontSize="17"/>
   <mx:Label x="60" y="57" width="160" id="labNikeName" color="#C52167" fontSize="17"/>
   <mx:Button x="228" y="8" label="searchWebService" width="131" click="requestWebService();"/>
   <mx:TextInput x="60" y="8" id="txtUserID"/>
 </mx:Canvas>

<mx:Canvas x="10" y="218" width="393" height="200" backgroundColor="#84DACF"> <mx:Label x="4" y="10" text="UserID:"/> <mx:Label x="60" y="83" width="160" id="labName" color="#C52167" fontSize="17"/> <mx:Label x="60" y="109" width="160" id="labPosition" color="#C52167" fontSize="17"/> <mx:Label x="60" y="57" width="160" id="labNikeName" color="#C52167" fontSize="17"/> <mx:Button x="228" y="8" label="searchWebService" width="131" click="requestWebService();"/> <mx:TextInput x="60" y="8" id="txtUserID"/> </mx:Canvas> 
   引入WebService组件（<mx:operation></mx:operation>节点定义WebService定义的方法信息（对应WSDL文件的方法描述）可以为多个）：
 

<mx:WebService id="uReqWebService"  wsdl="http://localhost:2222/FlexService/SearchUserService.asmx?WSDL">
   <mx:operation name="SearchUserName" resultFormat="object" fault="serviceReqFault(event)" result="serviceReqResult(event)">
  </mx:operation>
 </mx:WebService>

<mx:WebService id="uReqWebService" wsdl="http://localhost:2222/FlexService/SearchUserService.asmx?WSDL"> <mx:operation name="SearchUserName" resultFormat="object" fault="serviceReqFault(event)" result="serviceReqResult(event)"> </mx:operation> </mx:WebService> 
    Flex中发送请求：

private function requestWebService():void
{
  uReqWebService.SearchUserName(txtUserID.text); //<mx:operation/>定义的方法
 labMsg.alpha = 1;
}

private function requestWebService():void { uReqWebService.SearchUserName(txtUserID.text); //<mx:operation/>定义的方法 labMsg.alpha = 1; }  

 

    Flex中接收返回数据:

private function serviceReqResult(e:ResultEvent):void
{
  if(e.result.toString().length > 0)
 {
  var arry:XML = XML(e.result);
   if(arry != null && arry.length()> 0)
  {
   labName.text = arry.children()[0];
   labNikeName.text = arry.children()[1];
   labPosition.text = arry.children()[2];
  }
 }
  else
 {
   labName.text = "";
   labNikeName.text = "";
   labPosition.text = "";
   Alert.show("查不到匹配的用户信息！");
 }
 labMsg.alpha = 0;
}

private function serviceReqResult(e:ResultEvent):void { if(e.result.toString().length > 0) { var arry:XML = XML(e.result); if(arry != null && arry.length()> 0) { labName.text = arry.children()[0]; labNikeName.text = arry.children()[1]; labPosition.text = arry.children()[2]; } } else { labName.text = ""; labNikeName.text = ""; labPosition.text = ""; Alert.show("查不到匹配的用户信息！"); } labMsg.alpha = 0; }  

 

    Flex中错误处理：

private function serviceReqFault(e:FaultEvent):void
{
  Alert.show("请求WebService出错！原因是：" + e.message);
 labMsg.alpha = 0;
}

private function serviceReqFault(e:FaultEvent):void { Alert.show("请求WebService出错！原因是：" + e.message); labMsg.alpha = 0; }
结果如图: