使用命令构建器SqlCommandBuilder

// 使用命令构建器SqlCommandBuilder

// SqlCmdBuilder.cs

using   System;

using   System.Data;

using   System.Data.SqlClient;

namespace   Ch13

{

      class   SqlCmdBuilder

    {

          static   void   Main(   string [] args)

        {

              string   strConn =   "server=.\\MSSQL2012;integrated security=true;database=Northwind" ;

              string   qry =   "select * from employees where employeeid>8"   ;           

            SqlConnection conn =   new   SqlConnection(strConn);

              try

            {

                SqlDataAdapter da =   new   SqlDataAdapter();

                da.SelectCommand =   new   SqlCommand(qry, conn);

                  // 为了使命令构建器工作，数据适配器的SelectCommand属性

                  // 必须包含一个查询，它返回数据库表的主键或唯一键。

                  // 如果该键不存在，就会生成InvalidOperation异常，不会生成命令。               

                  // 不必写带参数的SQL，以及为SqlCommand添加参数映射的代码。

                  // 创建命令构建器。

                SqlCommandBuilder cb =   new   SqlCommandBuilder(da);

                DataSet ds =   new   DataSet();

                da.Fill(ds,   "emp" );

                DataTable dt = ds.Tables[   "emp" ];

                  Console .WriteLine(   "添加前" );

                  foreach   (DataRow row   in   dt.Rows)

                {

                      Console .WriteLine(   "{0} {1} {2} {3}"

                        , row[   "employeeid" ].ToString().PadRight(5)

                        , row[   "firstname" ].ToString().PadRight(15)

                        , row[   "lastname" ].ToString().PadRight(15)

                        , row[   "city" ]);

                }

                  // 添加新行

                DataRow newrow = dt.NewRow();

                newrow[   "firstname" ] =   "张"   ;

                newrow[   "lastname" ] =   "三"   ;

                newrow[   "titleofcourtesy" ] =   "先生"   ;

                newrow[   "city" ] =   "深圳"   ;

                newrow[   "country" ] =   "中国"   ;

                dt.Rows.Add(newrow);

                  // 由于新行是添加到内存表，因此employeeid是未知的，不会显示

                  Console .WriteLine(   "添加后" );

                  foreach   (DataRow row   in   dt.Rows)

                {

                      Console .WriteLine(   "{0} {1} {2} {3}"

                        , row[   "employeeid" ].ToString().PadRight(5)

                        , row[   "firstname" ].ToString().PadRight(15)

                        , row[   "lastname" ].ToString().PadRight(15)

                        , row[   "city" ]);

                }

                  // 提交到数据库               

                da.Update(ds,   "emp" );

            }

              catch (   Exception   ex)

            {

                  Console .WriteLine(   "出错了:"   + ex);

            }

              finally

            {

                conn.Close();

                  Console .ReadLine();

            }

        }

    }

}

---------------------

添加前

9     Anne            Dodsworth       London

添加后

9     Anne            Dodsworth       London

      张               三               深圳

来自为知笔记(Wiz)

转载于:https://www.cnblogs.com/bloodfist/p/3278860.html