SilverLight调用WebService的方法
在我们添加Service Reference的时候，可能不知道该服务最终会被部署到什么位置，或者该服务可能被迁移，此时我们可以使用以下手段进行Service的调用，提高代码编写的灵活性。
步骤1：修改宿主Web页面的代码,将服务地址以初始化参数方式传入。
<form id="form1" runat="server" style="height:100%">
<div id="silverlightControlHost">
<object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%">
...
<param name="InitParams" value="serviceAddress=http://localhost/services/myservices.asmx" />
<a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=3.0.40624.0" style="text-decoration:none">
<img src="http://go.microsoft.com/fwlink/?LinkId=108181" alt="Get Microsoft Silverlight" style="border-style:none"/>
</a>
</object><iframe id="_sl_historyFrame" style="visibility:hidden;height:0px;width:0px;border:0px"></iframe></div>
</form>
<div id="silverlightControlHost">
<object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%">
...
<param name="InitParams" value="serviceAddress=http://localhost/services/myservices.asmx" />
<a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=3.0.40624.0" style="text-decoration:none">
<img src="http://go.microsoft.com/fwlink/?LinkId=108181" alt="Get Microsoft Silverlight" style="border-style:none"/>
</a>
</object><iframe id="_sl_historyFrame" style="visibility:hidden;height:0px;width:0px;border:0px"></iframe></div>
</form>
步骤2：添加Service引用并注册调用远程方法的事件处理。
添加Service的引用不必赘述.但此处添加Service Reference的目的仅在于获得远程方法的命名空间等程序结构信息。
如果我们的Silverlight程序主页面名叫MainPage,则在MainPage.xaml.cs中添加如下代码：
public void InitializeServices(string serviceAddress)
{
BasicHttpBinding basicBinding = new BasicHttpBinding();
CustomBinding binding = new CustomBinding(basicBinding);
BindingElement binaryElement = new BinaryMessageEncodingBindingElement();
EndpointAddress endPoint = new EndpointAddress(serviceAddress);
MyService.MyServicesSoapClient serviceClient = (MyServicesSoapClient)Activator.CreateInstance(typeof(MyServicesSoapClient), binding, endPoint);
serviceClient.MyRemoteMethodCompleted += new EventHandler<MyService.MyRemoteMethodCompletedEventArgs>(serviceClient_MyRemoteMethodCompleted);
serviceClient.MyRemoteMethodAsync();//调用远程方法
}
{
BasicHttpBinding basicBinding = new BasicHttpBinding();
CustomBinding binding = new CustomBinding(basicBinding);
BindingElement binaryElement = new BinaryMessageEncodingBindingElement();
EndpointAddress endPoint = new EndpointAddress(serviceAddress);
MyService.MyServicesSoapClient serviceClient = (MyServicesSoapClient)Activator.CreateInstance(typeof(MyServicesSoapClient), binding, endPoint);
serviceClient.MyRemoteMethodCompleted += new EventHandler<MyService.MyRemoteMethodCompletedEventArgs>(serviceClient_MyRemoteMethodCompleted);
serviceClient.MyRemoteMethodAsync();//调用远程方法
}
步骤3：修改App.xaml.cs，添加Application.Startup事件处理方法Application_Startup。
private void Application_Startup(object sender, StartupEventArgs e)
{
this.RootVisual = new MainPage();
string serviceAddress = e.InitParams["serviceAddress"].ToString();
(this.RootVisual as MainPage).InitializeServices(serviceAddress);
}
{
this.RootVisual = new MainPage();
string serviceAddress = e.InitParams["serviceAddress"].ToString();
(this.RootVisual as MainPage).InitializeServices(serviceAddress);
}
OK，至此，我们已经实现了在程序启动时调用一个MyRemoteMethod方法。以上代码稍加改动，我们就可以在程序的任意位置以这种方式调用远程方法了。
此方法对WCF Service的调用也有效，手段类似，实现略有不同。
