在 C# 中使用 OData 時,處理數據關聯的方法與處理一般的數據關聯類似。以下是一些基本步驟:
Customer
和 Order
,它們之間存在一對多的關聯。你需要為這兩個實體定義模型類,如下所示:public class Customer
{
public int Id { get; set; }
public string Name { get; set; }
public List<Order> Orders { get; set; }
}
public class Order
{
public int Id { get; set; }
public string OrderNumber { get; set; }
public int CustomerId { get; set; }
public Customer Customer { get; set; }
}
WebApiConfig.cs
文件中添加以下內容:config.MapODataServiceRoute(
name: "ODataRoute",
routePrefix: "api",
model: GetModel(),
routingConventions: new[] { new EntitySetRoutingConvention() });
WebApiConfig.cs
文件中添加以下內容:public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
// ... 其他配置代碼 ...
config.Routes.MapODataRoute(
name: "ODataRoute",
routePrefix: "api",
model: GetModel(),
routingConventions: new[] { new EntitySetRoutingConvention() });
}
private static IEdmModel GetModel()
{
ODataModelBuilder builder = new ODataModelBuilder();
builder.EntitySet<Customer>("Customers");
builder.EntitySet<Order>("Orders");
// 自定義關聯查詢
builder.Entity<Customer>().HasMany(c => c.Orders).WithRequired(o => o.Customer);
return builder.GetEdmModel();
}
}
GET http://localhost:端口號/api/Customers?$expand=Orders
這將返回與每個客戶關聯的訂單信息。