上图中红框标记部分的部分页面页容如下(SearchBar.ascx):


<table border="0" cellspacing="2" cellpadding="2">
<tr>
<td align="right" nowrap="nowrap" class="boldWhite">Food Type </td>
<td align="left">
<asp:ObjectDataSource ID="RestaurantCategoryDataSource" runat="server" SelectMethod="SelectAll" TypeName="DinnerNow.RestaurantCategoryDataSource"/>
<asp:DropDownList ID="restaurantCategoryList" runat="server"
DataSourceID="RestaurantCategoryDataSource" DataTextField="Description"
DataValueField="RestaurantId"/>
</td>
</tr>
</table>

<table border="0" cellspacing="2" cellpadding="2">
<tr>
<td align="right" class="boldWhite">Meal</td>
<td align="left">
<asp:ObjectDataSource ID="MenuTypeDataSource" runat="server" SelectMethod="SelectAll" TypeName="DinnerNow.MenuTypeDataSource"/>
<asp:DropDownList ID="menuTypeList" runat="server"
DataSourceID="MenuTypeDataSource" DataTextField="MenuTypeName"
DataValueField="MenuTypeName" />
</td>
</tr>
</table>



可以看出菜单下拉框选项使用ObjectDataSource方式进行加载，而页面代码中的下列两条语句是所加载类型的说明:
TypeName="DinnerNow.RestaurantCategoryDataSource'
TypeName="DinnerNow.MenuTypeDataSource"

　 这两个类型我们可以在下列路径下找到:
DinnerNow.WebUX\Code\DataSources\RestaurantCategoryDataSource.cs
DinnerNow.WebUX\Code\DataSources\MenuTypeDataSource.cs

它们两个的功能就是调用相应的SelectAll方法如下(仅以MenuTypeDataSource.cs为例)：

MenuTypeDataSource.cs




public IEnumerable<RestaurantCategory> SelectAll()
{
try
{
using (MenuSearchServiceClient client = new MenuSearchServiceClient("WSHttpBinding_IMenuSearchService"))
{
return client.GetRestaurantCategories();
}
}
catch (Exception)
{
//@TODO: Need to put some error handling in here
}
return null;
}


因为代码太简单没什么可说的，下面就根据其所请求的服务绑定项"WSHttpBinding_IMenuSearchService",　在web.config
中查找到如下配置节:

<endpoint address="http://localhost/DinnerNow/service/MenuSearch.svc" binding="wsHttpBinding"
bindingConfiguration="WSHttpBinding_IMenuSearchService" contract="MenuSearchService.IMenuSearchService"
name="WSHttpBinding_IMenuSearchService">
<identity>
<servicePrincipalName value="host" />
</identity>
</endpoint>
而相关的MenuSearch.svc（执行）文件就是其所引用的服务地址．好的，看清了这一块之后，我们切换到刚才所说的第二
个解决方案中（DinnerNow - ServicePortfolio2.sln），看一下这个SVC中是如何执行相应逻辑的:)

在DinnerNow - ServicePortfolio2.sln中的DinnerNow.ServiceHost项目是服务配置站点，我们可从该站点的web.config
文件中找出如下内容:
......

<service behaviorConfiguration="DinnerNow.Services.MenuSearchServiceBehavior"
name="DinnerNow.Services.MenuSearchService">
<endpoint address="" binding="wsHttpBinding" contract="DinnerNow.Services.IMenuSearchService" />