datagridview 增加数据行、修改数据行

【实例截图】

【核心代码】

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.OleDb;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace Datagridview修改删除
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            dataGridView1.AutoGenerateColumns = false;
            mydatebind();
        }
        string connstr = "provider=microsoft.jet.oledb.4.0;data source="   Application.StartupPath   "\\tke.mdb";

        public void mydatebind() {
            OleDbConnection conn = new OleDbConnection(connstr);
            conn.Open();
            OleDbDataAdapter cmd = new OleDbDataAdapter("select * from tbl_users", conn);
            DataSet rs = new DataSet();
            cmd.Fill(rs, "Myuser");
            dataGridView1.DataSource = rs.Tables["Myuser"].DefaultView;
            rs = null;
            cmd = null;
            conn.Close();
            conn = null;
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            
        }

        private void dataGridView1_CellValueChanged(object sender, DataGridViewCellEventArgs e)
        {
            if (e.RowIndex >= 0) {
                string Uid = dataGridView1.Rows[e.RowIndex].Cells["user_id"].FormattedValue.ToString();
                string Uname = dataGridView1.Rows[e.RowIndex].Cells["user_name_cn"].FormattedValue.ToString();
                string Uregion = dataGridView1.Rows[e.RowIndex].Cells["user_region"].FormattedValue.ToString();
                string Uemail = dataGridView1.Rows[e.RowIndex].Cells["user_email"].FormattedValue.ToString();
                string sql;
                if (e.RowIndex > mycount() - 1 && (Uid == null || Uid==""))
                {
                    sql = "insert into tbl_users(user_id,user_name_cn,user_region,user_email) values("   mycount()   1   ",'"   Uname   "','"   Uregion   "','"   Uemail   "')";
                }
                else {
                    sql = "update tbl_users set user_name_cn='"   Uname   "',user_region='"   Uregion   "',user_email='"   Uemail   "' where user_id="   Uid;
                }
                OleDbConnection connd = new OleDbConnection(connstr);
                connd.Open();
                OleDbCommand cmdd = new OleDbCommand(sql, connd);
                cmdd.ExecuteNonQuery();
                cmdd = null;
                connd.Close();
                connd = null;
                mydatebind();
            }
  
        }

        public int mycount() {
            int coun;
            OleDbConnection connc = new OleDbConnection(connstr);
            connc.Open();
            OleDbCommand cmdc = new OleDbCommand("select count(user_id) from tbl_users", connc);
            string cou = cmdc.ExecuteScalar().ToString ();
            if (cou != "" && cou != null)
            {
                coun = Convert.ToInt16(cou);
            }
            else {
                coun = 0;
            }
            cmdc = null;
            connc.Close();
            connc = null;
            return coun;
  
        }

        //将SelectMode设置为FullRowSelect
        private void dataGridView1_UserDeletingRow(object sender, DataGridViewRowCancelEventArgs e)
        {
                string Uid = this.dataGridView1.CurrentRow.Cells["user_id"].FormattedValue.ToString();
                OleDbConnection conne = new OleDbConnection(connstr);
                conne.Open();
                OleDbCommand cmde = new OleDbCommand("delete from tbl_users where user_id="   Uid, conne);
                cmde.ExecuteNonQuery();
                cmde = null;
                conne.Close();
                conne = null;
        }

    }
}