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  • Entity Framework 学习中级篇4—存储过程(下)

    EF中,各个实体的插入、更新和删除也都通过使用存储过程来完成,以便提高点性能。这个类似于数据集。其步骤是:先定义存储过程,然后在VS的可视化设计器,设置存储过程映射即可。

    下面,以为Supplier实体映射存储过程为例。

    分别建立插入、更新和删除存储过程。

    InsertSuppliers存储过程定义如下:

    CREATE PROCEDURE [dbo].[InsertSuppliers]

        -- Add the parameters for the stored procedure here

    @CompanyName nvarchar(40),

    @ContactName nvarchar(30),

    @ContactTitle nvarchar(30),

    @Address nvarchar(60),

    @City nvarchar(15),

    @Region nvarchar(15),

    @PostalCode nvarchar(10),

    @Country nvarchar(15),

    @Phone nvarchar(24),

    @Fax nvarchar(24),

    @HomePage ntext

    AS

    BEGIN

        -- SET NOCOUNT ON added to prevent extra result sets from

        -- interfering with SELECT statements.

        SET NOCOUNT ON;

        INSERT INTO Suppliers(CompanyName,ContactName,ContactTitle,Address,City,Region,PostalCode,Country,Phone,Fax,HomePage)

        VALUES(@CompanyName,@ContactName,@ContactTitle,@Address,@City,@Region,@PostalCode,@Country,@Phone,@Fax,@HomePage);

        SELECT SCOPE_IDENTITY() AS SupplierID;

    END

    DeleteSuppliers存储过程定义如下:

    CREATE PROCEDURE [dbo].[DeleteSuppliers]

        -- Add the parameters for the stored procedure here

    @SupplierID int

    AS

    BEGIN

        -- SET NOCOUNT ON added to prevent extra result sets from

        -- interfering with SELECT statements.

        SET NOCOUNT ON;

        DELETE Suppliers WHERE SupplierID=@SupplierID

    END

    UpdateSuppliers存储过程定义如下:

    CREATE PROCEDURE [dbo].[UpdateSuppliers]

     -- Add the parameters for the stored procedure here

    @SupplierID int,

    @CompanyName nvarchar(40),

    @ContactName nvarchar(30),

    @ContactTitle nvarchar(30),

    @Address nvarchar(60),

    @City nvarchar(15),

    @Region nvarchar(15),

    @PostalCode nvarchar(10),

    @Country nvarchar(15),

    @Phone nvarchar(24),

    @Fax nvarchar(24),

    @HomePage ntext

    AS

    BEGIN

     -- SET NOCOUNT ON added to prevent extra result sets from

     -- interfering with SELECT statements.

     SET NOCOUNT ON;

        UPDATE Suppliers SET CompanyName=@CompanyName,ContactName=@ContactName,ContactTitle=@ContactTitle,Address=@Address,City=@City,Region=@Region,PostalCode=@PostalCode,Country=@Country,Phone=@Phone,Fax=@Fax,HomePage=@HomePage

     WHERE SupplierID=@SupplierID

    END

    然后,在VS可视化设计器中,打开实体模式edmx文件,然后在Suppliers实体上鼠标右键à“存储过程映射”,然后在在分别设置存储过程即可。如下图所示:

    至此,存储过程映射完毕。我们下面来具体的使用,代码如下:

    使用存储过程Insert:

    [Test]

            public void SPInsert()

            {

                using (var db = new NorthwindEntities1())

                {

                    var supplier = new Suppliers();

                    supplier.CompanyName = "cnblogs";

                    supplier.ContactName = "xray2005";

                    supplier.ContactTitle = "net";

                    supplier.City = "成都";

                    supplier.Region = "四川";

                    supplier.Country = "中国";

                    supplier.PostalCode = "600041";

                    supplier.Phone = "028-8001";

                    supplier.Fax = "028-8002";

                    supplier.HomePage = "http://xray2005.cnblogs.com";

                    db.AddToSuppliers(supplier);

                    db.SaveChanges();

     

                }

            }

    使用存储过程Update:

            [Test]

            public void SPUpdate()

            {

                using (var db = new NorthwindEntities1())

                {

                    var supplier = db.Suppliers.FirstOrDefault(s => s.SupplierID == 30);

                    Assert.IsNotNull(supplier);

                    supplier.CompanyName = "CNBLOGS";

                    supplier.ContactName = "xray2005";

                    supplier.ContactTitle = "♂风风车.net";

                    supplier.City = "成都";

                    supplier.Region = "四川";

                    supplier.Country = "China";

                    supplier.PostalCode = "600040";

                    supplier.Phone = "028-1008611";

                    supplier.Fax = "028-10086";

                    supplier.HomePage = "http://www.cnblogs.com/xray2005";

                    db.SaveChanges();

     

                }

            }

    使用存储过程Delete:

            [Test]

            public void SPDelete()

            {

                using (var db = new NorthwindEntities1())

                {

                    var supplier = db.Suppliers.FirstOrDefault(s => s.SupplierID == 31);

                    Assert.IsNotNull(supplier);

                    db.DeleteObject(supplier);

                    db.SaveChanges();

                    var supplier1 = db.Suppliers.FirstOrDefault(s => s.SupplierID == 31);

                    Assert.IsNull(supplier1);

                }

            }

    至此,实体存储过程映射介绍完毕。本节,内容比较简单。

     
         本文版权归作者所有,欢迎转载,但未经作者同意必须保留此段声明,且在文章页面明显位置给出原文连接,否则保留追究法律责任的权利。
     
    原文链接:http://www.cnblogs.com/xray2005/archive/2009/06/05/1496732.html
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  • 原文地址:https://www.cnblogs.com/xwj517537691/p/3126948.html
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