C#与ACCESS

1.配置ACCESS链接

    public class DataManagement
    {
        private static OleDbConnection connection;
        public static OleDbConnection Connection
        {
            get
            {
                if (connection == null)
                {
                    connection = new OleDbConnection(System.Configuration.ConfigurationManager.ConnectionStrings["ProcessSoftware.Properties.Settings.ProcessSoftwareConnectionString"].ConnectionString);
                    connection.Open();
                }
                else if (connection.State == System.Data.ConnectionState.Closed)        //关闭
                {
                    connection.Open();
                }
                else if (connection.State == System.Data.ConnectionState.Broken)     //中断
                {
                    connection.Close();
                    connection.Open();
                }
                return connection;
            }
        }
    }

 2.新增、修改、删除查询

        private void button1_Click(object sender, EventArgs e)
        {
            if (textBox1.Text != "")
            {
                OleDbConnection connection = DataManagement.Connection;
                string sql = "insert into [user](username,logintime) values('" + textBox1.Text+"','"+ DateTime.Now.ToString() + "')";
                OleDbCommand cmd = new OleDbCommand(sql, connection);
                cmd.ExecuteNonQuery();//新增\修改\删除用这个
                connection.Close();
                Program.username = textBox1.Text;
            }
            else
            {
                MessageBox.Show("请输入姓名");
            }
           
        }

 3.从ACCESS中查询数据

        public void loaddata(int currentnum)
        {
            OleDbConnection connection = DataManagement.Connection;
            string sql = "select * from zxd_daqcl";
            OleDbDataAdapter oleDap = new OleDbDataAdapter(sql, connection);
            DataSet ds = new DataSet();
            oleDap.Fill(ds, "档案前处理");
            //将查询数据显示到dataGridView1
            dataGridView1.DataSource = ds.Tables[0].DefaultView;
            //设置dataGridView隐藏列
            dataGridView1.Columns[0].Visible = false;
            if (currentnum != 0)
            {
                dataGridView1.CurrentCell = dataGridView1.Rows[currentnum].Cells[1];
            }
            connection.Close();
        }

 4.所需命名空间：
using System.Data.OleDb;
using System.Configuration;