Setp 1 : First Start visual Studion and Create new Project in C# Lnguages

Step 2 : Go Design Form and put a gridview and a button on Form ;

Step 3 : Use Namespace

using System.Data;
using System.Data.OleDb;

Setp 4 : Create Event og Button Write code in

private void Button1_Click(object sender, EventArgs e)
{
 OpenFileDialog op = new OpenFileDialog();
op.Filter = "Excel 97 - 2003|*.xls|Excel 2007|*.xlsx";
 if (op.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
 if (File.Exists(op.FileName))
{
 string[] Arr = null;
Arr = op.FileName.Split('.');
 if (Arr.Length > 0)
{
 if (Arr[Arr.Length - 1] == "xls")
sConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" +
op.FileName + ";Extended Properties='Excel 8.0;HDR=Yes;IMEX=1'";
}
 else if (Arr[Arr.Length - 1] == "xlsx")
{
sConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + op.FileName + ";Extended Properties='Excel 12.0 Xml;HDR=YES';";
}
}
FillData();
}
}
}
public string sConnectionString;
private void FillData()
{
 if (sConnectionString.Length > 0)
{
 OleDbConnection cn = new OleDbConnection(sConnectionString);
{
cn.Open();
 DataTable dt = new DataTable();
 OleDbDataAdapter Adpt = new OleDbDataAdapter("select * from [sheet1$]", cn);
Adpt.Fill(dt);
DataGridView1.DataSource = dt;
}
 catch (Exception ex)
{
}
}
}

Screen Shot

excel.png