整理一下级联更新和删除 c#调用返回值

use master  go  IF exists(select 1 from sysdatabases where name='temp')BEGIN		DROP DATABASE tempENDcreate database tempgouse tempgo--drop table  ProductInfocreate table ProductInfo(	ProductId int  primary key ,	ProductName varchar(20),  	) create table ProductDetails(	id int identity(1,1) primary key,	num varchar(100) , 	ProductId int,	foreign key (ProductId) references ProductInfo(ProductId) on delete cascade on update cascade) insert ProductInfo values (1,'Think')insert ProductInfo values(2,'TCL')insert ProductInfo values(3,'HTC') insert ProductDetails values('T420',1)insert ProductDetails values('Xo1',1)insert ProductDetails values('TVoo1',2)insert ProductDetails values('TPhone',2)insert ProductDetails values('One',3)insert ProductDetails values('Buffer',3) alter table 表名add constraint 外键名foreign key(字段名) references 主表名(字段名)on delete cascade --删除on update cascade --更新--查看现有数据select * from ProductInfoselect * from ProductDetails--更改update ProductInfo set ProductId=5  where ProductName='Think'select * from ProductInfoselect * from ProductDetails--删除delete from ProductInfo where ProductId=5select * from ProductInfoselect * from ProductDetails

　　

第一种方法:C#代码:protected void btnBack_Click(object sender, EventArgs e){        //调用存储过程        stringconStr=ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ToString();        SqlConnection conn = new SqlConnection(conStr);        SqlCommand cmd = new SqlCommand();        cmd.CommandText = "MyProc";        cmd.CommandType = CommandType.StoredProcedure;        cmd.Connection=conn;        conn.Open();        SqlParameter sp = new SqlParameter("@ID", SqlDbType.Int);        sp.Value = int.Parse("3");        cmd.Parameters.Add(sp);         //定义输出参数        SqlParameter returnValue = new SqlParameter("@returnValue", SqlDbType.Int);        returnValue.Direction = ParameterDirection.ReturnValue;        cmd.Parameters.Add(returnValue);        cmd.ExecuteNonQuery();                conn.Close(); }存储过程如下:create procedure MyProc(     @ID int)as  return 1 go注意,(return)这种方式 只能返加数值类型 第二种方法:protected void btnBack_Click(object sender, EventArgs e){        //调用存储过程        string conStr = System.Configuration.ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ToString();        SqlConnection conn = new SqlConnection(conStr);        SqlCommand cmd = new SqlCommand();        cmd.CommandText = "MyProc";        cmd.CommandType = CommandType.StoredProcedure;        cmd.Connection=conn;        conn.Open();        SqlParameter sp = new SqlParameter("@ID", SqlDbType.Int);        sp.Value = int.Parse("3");        cmd.Parameters.Add(sp);         //定义输出参数        sp = new SqlParameter("@outputValue", SqlDbType.NVarChar,50);        sp.Direction = ParameterDirection.Output;        cmd.Parameters.Add(sp);        cmd.ExecuteNonQuery();                conn.Close();     } 存储过程如下:alter procedure MyProc(     @ID int,     @outputValue nvarchar(50) output )as Select @outputValue='aa'go