步步为营-42-通过DataAdapter实现增删查改

说明:通过DataAdapter或者dataset连接数据库,实现对数据增删改查操作.

 以前写过一篇步步为营-23-通过GridView实现增删改

1:SqlDataAdapter  DataTable实现

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace DataView
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
        }

        private void MainForm_Load(object sender, EventArgs e)
        {
            //01-创建配置文件  添加引用
            //02-设置连接字符串]
            string connStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;
            //03 创建连接字符串
            using (SqlConnection conn = new SqlConnection(connStr))
            {
                //04-创建数据库操作脚本
                string sqlStr = "select EmpId, Pwd, StuName, StuAge, Delflag, ClassNo from UserInfo";
                using (SqlDataAdapter sda = new SqlDataAdapter(sqlStr,conn))
                {
                    //05-隆重介绍一下Adapter-适配器
                    //05-01判断sqlConnection是否初始化
                    //05-02初始化Select Command对象
                    //05-03 通过cmd对象执行返回SQLdataReader对象
                    //05-04 读取数据,填充到datatreader上
                    DataTable dt =  new DataTable();
                    sda.Fill(dt);
                    //05-创建实体模型,对数据进行封装
                    List<UserINfo> userList = new List<UserINfo>();
                    foreach (DataRow dataRow in dt.Rows)
                    {
                        //封装数据
                        userList.Add(new UserINfo() { EmpId = int.Parse(dataRow["EmpId"].ToString()),
                                                      StuName = dataRow["StuName"].ToString(),
                                                      StuAge = int.Parse(dataRow["StuAge"].ToString())
                                                    });
                      
                        
                    }
                    //06-设置数据源
                    this.dataGridView1.DataSource = userList;

                }
            }
           



        }
    }
}

2:运行效果

3SqlDataAdapter  DataSet实现

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace DataView
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
        }

        private void MainForm_Load(object sender, EventArgs e)
        {
            //01-创建配置文件  添加引用
            //02-设置连接字符串]
            string connStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;
            //03 创建连接字符串
            using (SqlConnection conn = new SqlConnection(connStr))
            {
                //04-创建数据库操作脚本
                string sqlStr = @"
                select ClassId, ClassName from ClassInfo;
                select EmpId, Pwd, StuName, StuAge, Delflag, ClassNo from UserInfo";
                using (SqlDataAdapter sda = new SqlDataAdapter(sqlStr,conn))
                {
                    //05-隆重介绍一下Adapter-适配器
                    //05-01判断sqlConnection是否初始化
                    //05-02初始化Select Command对象
                    //05-03 通过cmd对象执行返回SQLdataReader对象
                    //05-04 读取数据,填充到datatreader上
                  
                    DataSet ds = new DataSet();
                    sda.Fill(ds);
                    List<UserINfo> userList = new List<UserINfo>();
                    foreach (DataRow dataRow in ds.Tables[1].Rows)
                    {
                        //封装数据
                        userList.Add(new UserINfo()
                        {
                            EmpId = int.Parse(dataRow["EmpId"].ToString()),
                            StuName = dataRow["StuName"].ToString(),
                            StuAge = int.Parse(dataRow["StuAge"].ToString())
                        });


                    }
                    this.dataGridView1.DataSource = userList;
                }
            }
           



        }
    }
}

 4 实现增删查改--通过SqlCommandBuilder

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace DataView
{
    public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }

        private void Form2_Load(object sender, EventArgs e)
        {
            //01-创建配置文件  添加引用
            //02-设置连接字符串]
            string connStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;
            //03 创建连接字符串
            using (SqlConnection conn = new SqlConnection(connStr))
            {
                //04-创建数据库操作脚本
                string sqlStr = @"select EmpId, Pwd, StuName, StuAge, Delflag, ClassNo from UserInfo";
                using (SqlDataAdapter sda = new SqlDataAdapter(sqlStr, conn))
                {


                    DataTable dt =new DataTable();
                    sda.Fill(dt);
                    
                    this.dataGridView1.DataSource = dt;
                }
            }




        }

        private void btnSave_Click(object sender, EventArgs e)
        {
            //把DataGridView的修改的数据保存到数据库中去。
            string connStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;

            //修改的sql一定要跟  查询的sql脚本一致。
            string sqlStr = @"select EmpId, Pwd, StuName, StuAge, Delflag, ClassNo from UserInfo";

            using (SqlDataAdapter adapter = new SqlDataAdapter(sqlStr, connStr))
            {
               //01-拿到修改之后的datatable对象
                DataTable dt = this.dataGridView1.DataSource as DataTable;
                //把修改完的内存表  映射到数据库中对应的表
                //SQLCommandBuilder帮助我们Adapter生成相关的command
                using (SqlCommandBuilder cmdBuilder = new SqlCommandBuilder(adapter))
                {
                    adapter.Update(dt);
                }
            }
        }
    }
}

5 实现增删查改--手动写

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace DataView
{
    public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }

        private void Form2_Load(object sender, EventArgs e)
        {
            //01-创建配置文件  添加引用
            //02-设置连接字符串]
            string connStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;
            //03 创建连接字符串
            using (SqlConnection conn = new SqlConnection(connStr))
            {
                //04-创建数据库操作脚本
                string sqlStr = @"select EmpId, Pwd, StuName, StuAge, Delflag, ClassNo from UserInfo";
                using (SqlDataAdapter sda = new SqlDataAdapter(sqlStr, conn))
                {


                    DataTable dt =new DataTable();
                    sda.Fill(dt);
                    
                    this.dataGridView1.DataSource = dt;
                }
            }




        }

        private void btnSave_Click(object sender, EventArgs e)
        {
            //把DataGridView的修改的数据保存到数据库中去。
            string connStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;

            //修改的sql一定要跟  查询的sql脚本一致。
            string sqlStr = @"select EmpId, Pwd, StuName, StuAge, Delflag, ClassNo from UserInfo";

            using (SqlConnection conn = new SqlConnection(connStr))
            {
                using (SqlDataAdapter adapter = new SqlDataAdapter(sqlStr, conn))
                {
                    //adapter.in
                    //拿到修改完了之后的DataTable对象
                    DataTable dt = this.dataGridView1.DataSource as DataTable; //

                    #region 手写 删除 SqlCommand
                    //删除的Command 
                    adapter.DeleteCommand = conn.CreateCommand();
                    adapter.DeleteCommand.CommandText = "delete from UserInfo where EmpId=@EmpId";

                    //执行删除操作，把 EmpId列的值 给@EmpId参数用。
                    adapter.DeleteCommand.Parameters.Add("@EmpId", SqlDbType.Int, 4, "EmpId");

                    #endregion

                    #region 手写 修改的 SqlCommand
                    adapter.UpdateCommand = conn.CreateCommand();
                    adapter.UpdateCommand.CommandText = "update  UserInfo set Pwd=@Pwd, StuName=@StuName,StuAge=@StuAge ,Delflag=@Delflag, ClassNo=@ClassNo where EmpId=@EmpId";

                    //执行更新操作
                    adapter.UpdateCommand.Parameters.Add("@EmpId", SqlDbType.Int, 4, "EmpId");
                    adapter.UpdateCommand.Parameters.Add("@Pwd", SqlDbType.NVarChar, 32, "Pwd");
                    adapter.UpdateCommand.Parameters.Add("@StuName", SqlDbType.NVarChar, 32, "StuName");
                    adapter.UpdateCommand.Parameters.Add("@StuAge", SqlDbType.Int, 4, "StuAge");
                    adapter.UpdateCommand.Parameters.Add("@Delflag", SqlDbType.Int, 4, "Delflag");
                    adapter.UpdateCommand.Parameters.Add("@ClassNo", SqlDbType.Int, 4, "ClassNo");
                    #endregion

                    #region 手写 新增 SqlCommand
                    adapter.InsertCommand = conn.CreateCommand();
                    adapter.InsertCommand.CommandText = "INSERT INTO UserInfo  (Pwd,StuName,StuAge,Delflag,ClassNo) VALUES (@Pwd,@StuName, @stuAge, @Delflag,@ClassNo)";

                    //执行更新操作
                    adapter.InsertCommand.Parameters.Add("@Pwd", SqlDbType.NVarChar, 32, "Pwd");
                    adapter.InsertCommand.Parameters.Add("@StuName", SqlDbType.NVarChar, 32, "StuName");
                    adapter.InsertCommand.Parameters.Add("@StuAge", SqlDbType.Int, 4, "StuAge");
                    adapter.InsertCommand.Parameters.Add("@Delflag", SqlDbType.Int, 4, "Delflag");
                    adapter.InsertCommand.Parameters.Add("@ClassNo", SqlDbType.Int, 4, "ClassNo");
                    #endregion

                    adapter.Update(dt);

                    #region 使用命令生成器

                    //找到表中，添加数据，生成一条insert ，Insert Command ExcuteNonQuery到数据库中。
                    //如果修改的：update
                    //delet...

                    ////把修改完的内存表dt 变化映射到数据库中的表的变化。
                    ////SqlCommandBuilder帮助我们的Adapter生成相关的CRUD  SqlCommand
                    //using (SqlCommandBuilder cmdBuilder = new SqlCommandBuilder(adapter))
                    //{
                    //    adapter.Update(dt);
                    //} 

                    #endregion
                }
            }//end  using Conn
            MessageBox.Show("保存成功");
        }
    }
}

增

删

改