How to create Auto ID using C# windows form with Acess Database

Let’s start with create a new windows form. 

We need one Label, one TextBox one button and one GridView.

The code is shown below:

using System;  

using System.Collections.Generic;  

using System.ComponentModel;  

using System.Data;  

using System.Drawing;  

using System.Linq;  

using System.Text;  

using System.Windows.Forms;  

using System.Data.OleDb;  

namespace idgenerator  

{  

    public partial class Form1 : Form  

    {  

        OleDbConnection connectiondb = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\C# Cor\database\mydatabase.accdb;Persist Security Info=False");  

        OleDbCommand com;  

        string str;  

        public Form1()  

        {  

            InitializeComponent();  

            new_id();  

            showdata();  

        }  

        private void Form1_Load(object sender, EventArgs e)  

        {  

        }  

        private void new_id()  

        {  

            if (connectiondb.State == ConnectionState.Closed)  

            {  

                connectiondb.Open();  

            }  

            str = "select max(admin_create_id) from tbl_user";  

            com = new OleDbCommand(str, connectiondb);  

            com.CommandType = CommandType.Text;  

            Int32 max = (Int32)com.ExecuteScalar();  

            label3.Text = (max + 1).ToString();  

            connectiondb.Close();  

        }  

        private void button1_Click(object sender, EventArgs e)  

        {  

            if (connectiondb.State == ConnectionState.Closed)  

            {  

                connectiondb.Open();  

            }  

            str = "insert into tbl_user (admin_create_id,sName) values (@admin_create_id,@sName)";  

            com = new OleDbCommand(str, connectiondb);  

            com.Parameters.AddWithValue("@admin_create_id", label3.Text);  

            com.Parameters.AddWithValue("@sName", textBox2.Text);  

            com.ExecuteNonQuery();  

            connectiondb.Close();  

            MessageBox.Show("Records Successfuly Inserted");  

            showdata();  

            new_id();  

        }  

        private void showdata()  

        {  

            if (connectiondb.State == ConnectionState.Closed)  

            {  

                connectiondb.Open();  

            }  

            string strSql = "Select admin_create_id,sName from tbl_user";  

            OleDbCommand cmd = new OleDbCommand(strSql, connectiondb);  

            cmd.CommandType = CommandType.Text;  

            OleDbDataAdapter da = new OleDbDataAdapter(cmd);  

            DataTable dt = new DataTable();  

            da.Fill(dt);  

            dataGridView1.DataSource = dt;  

            connectiondb.Close();  

        }  

    }  

}  

Result