《Entity Framework 6 Recipes》中文翻译——第十章EntityFramework存储过程处理（四）

从存储过程返回一个复杂类型

问题

　　您希望在模型使用存储过程中返回一个复杂类型。

解决方案

　　让我们说，你有一个Employee实体模型。Employee包含员工的身份证、名称和一个复杂的地址类型，保存员工的地址、城市、州和邮政编码（address, city, state, 和 ZIPcode）。复杂类型的名称是员工地址。在员工实体的属性是简单的地址。

　　您要使用存储过程返回雇员地址复杂类型的实例的集合。存储过程返回的地址如下：

create procedure [dbo].[GetEmployeeAddresses]
(@city varchar(50))
as
begin
        select [Address], City, [State], ZIPcode
        from Employee where City = @city
end

1、右键单击设计面，并从数据库中选择更新模型。在对话框中，选择“GetEmployeeAddresses”存储过程。单击“完成”将存储过程添加到模型中。

2、右键单击设计图面上，并选择“添加➤函数导入。选择从所存储的过程名称下拉列表中GetEmployeeAddresses。在函数导入名称文本框中，输入GetEmployeeAddresses。这将是模型中的方法的名称。选择“复杂的返回类型”，并在下拉菜单中选择“ EmployeeAddress”。单击“确定”。

3、调用存储过程

using (var context = new School5Entities())
            {
                var emp1 = new Employee
                {
                    Name = "Lisa Jefferies",
                    Address = new EmployeeAddress
                    {
                        Address = "100 E. Main",
                        City = "Fort Worth",
                        State = "TX",
                        ZIPcode = "76106"
                    }
                };
                var emp2 = new Employee
                {
                    Name = "Robert Jones",
                    Address = new EmployeeAddress
                    {
                        Address = "3920 South Beach",
                        City = "Fort Worth",
                        State = "TX",
                        ZIPcode = "76102"
                    }
                };
                var emp3 = new Employee
                {
                    Name = "Steven Chue",
                    Address = new EmployeeAddress
                    {
                        Address = "129 Barker",
                        City = "Euless",
                        State = "TX",
                        ZIPcode = "76092"
                    }
                };
                var emp4 = new Employee
                {
                    Name = "Karen Stevens",
                    Address = new EmployeeAddress
                    {
                        Address = "108 W. Parker",
                        City = "Fort Worth",
                        State = "TX",
                        ZIPcode = "76102"
                    }
                };
                context.Employees.Add(emp1);
                context.Employees.Add(emp2);
                context.Employees.Add(emp3);
                context.Employees.Add(emp4);
                context.SaveChanges();

            }
            using (var context = new School5Entities())
            {
                Console.WriteLine("Employee addresses in Fort Worth, TX");
                foreach (var address in context.GetEmployeeAddresses("Fort Worth"))
                {
                    Console.WriteLine("{0}, {1}, {2}, {3}", address.Address,
                                       address.City, address.State, address.ZIPcode);
                }

            }

执行结果