How many ways can read Excel file in C#.

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.OleDb;

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
string path;
path = "C:\\";
DataTable grdDataSet = new DataTable();
grdDataSet= GetDataTableFromExcel(path);
GridView1.DataSource = grdDataSet;
GridView1.DataBind();
}
public static DataTable GetDataTableFromExcel(string SourceFilePath)
{
string ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" +
"Data Source=" + SourceFilePath + ";" +
"Extended Properties=\"Text;HDR=YES;\"";

using (OleDbConnection cn = new OleDbConnection(ConnectionString))
{
cn.Open();

DataTable dbSchema = cn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
if (dbSchema == null || dbSchema.Rows.Count < 1)
{
throw new Exception("Error: Could not determine the name of the first worksheet.");
}

string WorkSheetName = dbSchema.Rows[0]["TABLE_NAME"].ToString();
// string WorkSheetName = "ExcelData.csv";
OleDbDataAdapter da = new OleDbDataAdapter("SELECT * FROM [" + WorkSheetName + "]", cn);
DataTable dt = new DataTable(WorkSheetName);
da.Fill(dt);
return dt;
}
}

}