OleDbDataAdapter provides the communication between the Dataset and the Data Source with the help of OleDbConnection Object . The OleDbConnection Object has no information about the data it retrieves . Similarly a Dataset has no knowledge of the Data Source where the data coming from. So the OleDbDataAdapter manage the communication between these two Objects.
OleDbDataAdapter is used to retrieve data from a data source and populate tables within a DataSet . The OleDbDataAdapter also resolves changes made to the DataSet back to the data source. The OleDbDataAdapter object allows us to populate Data Tables in a DataSet. We can use Fill method of the OleDbDataAdapter for populating data in a Dataset. The following c# Source Code shows a simple program that uses OleDbDataAdapter to retrieve data from Data Source with the help of OleDbConnection object and populate the data in a Dataset.
using System;
using System.Data;
using System.Data.OleDb;
using System.Windows.Forms;
namespace WindowsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
string connetionString = null;
OleDbConnection connection ;
OleDbDataAdapter oledbAdapter ;
DataSet ds = new DataSet();
int i = 0;
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;";
connection = new OleDbConnection(connetionString);
try
{
connection.Open();
oledbAdapter = new OleDbDataAdapter("select * from users", connection);
oledbAdapter.Fill(ds);
oledbAdapter.Dispose();
connection.Close();
for (i = 0; i <= ds.Tables[0].Rows.Count - 1; i++)
{
MessageBox.Show (ds.Tables[0].Rows[i].ItemArray[0].ToString ());
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
}
}