How to connect Excel DB using C# .Net

//Step 1: Browse the Excel file 
//The Button(Browse) to "open the FileDialog Box" the path stored in your "Textbox1.text" my textbox name is "txtsearch.text" you can assign any name as your wish..
// 'DataTable' is the class stores the rows and columns of data.data comes any where from method,database,memory..
//getDataFromXLS(filepath)//reading data from excel Filepath(txtsearch.txt)

 private void button1_Click(object sender, EventArgs e)  
        {            
            OpenFileDialog ofd = new OpenFileDialog();
            DialogResult dr = ofd.ShowDialog();
            if (dr == DialogResult.OK)
            {
                txtsearch.Text = ofd.FileName;
                DataTable test = getDataFromXLS(txtsearch.Text);  
                if (test != null)                                
                    dataGridView1.DataSource = test;             
            }     
        }
//Step 2: once the file path is assigned
//step 3: Toolbox->datagridview and resize as your wish
//step 3: Xl into Gridview
 private DataTable getDataFromXLS(string strFilePath)
          {
            try
             {   
                string strConnectionString = "";
                strConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" +"Data Source=" + strFilePath + "; Jet OLEDB:Engine Type=5;" +"Extended Properties=Excel 8.0;";                                
                OleDbConnection cnCSV = new OleDbConnection(strConnectionString);    //set the new oledb connection as like sql           
                cnCSV.Open();                
                OleDbCommand cmdSelect = new OleDbCommand(@"SELECT * FROM [Sheet1$]", cnCSV);//here the oledbconnection where the sheet name is available or not.. if your sheet name is "test" change the setting as [test$] like..      
                OleDbDataAdapter daCSV = new OleDbDataAdapter();//oledbadapter it communicate between dataset and data sources with help of oledbconnection.
//oledbconnection object has no information data it retrives.same dataset has no knowledge datasource where the data commming from.
//oledbdataadapter manage the communicate the 2 obj..          
                daCSV.SelectCommand = cmdSelect;                    
                DataTable dtCSV = new DataTable();
                daCSV.Fill(dtCSV);               
                cnCSV.Close();
                daCSV = null;
                MessageBox.Show("Copied");                    
                return dtCSV;
             }
             catch(Exception ex)
                {
                    MessageBox.Show(ex.Message);
                    return null;                   
                }               
           }
//Step 5: Grid view into DB

private void button1_Click_1(object sender, EventArgs e)
                {                    
       for (int i = 0; i <= dataGridView1.Rows.Count - 1; i++)//to read the date atlast row in gridview
                        {
   
  string Query = "Insert into EFCD_3013(Dok_Nr,Bl)Values('" + dataGridView1.Rows[i].Cells["Dok_Nr"].Value + "','" + dataGridView1.Rows[i].Cells["Bl"].Value + "')";// add the column as your wish. note : make your xl column name and sql column name are same.                          
                            try
                            {
                                string Connection = null;
                                Connection = "/*Your connection string*/";
                                SqlConnection Con = new SqlConnection(Connection);
                                Con.Open();
                                SqlCommand Cmd = new SqlCommand(Query, Con);                              
                                Cmd.ExecuteNonQuery();
                                Con.Close();
                                  
                            }
                            catch (Exception ex)
                            {
                                MessageBox.Show(ex.Message);
                            }  }                                                                                              
                    }