how can we update database thru datagrid

Try this code

public partial class MainForm: Form {
  public MainForm() {
    InitializeComponent();
  }

  private void MainForm_Load(
    object sender, EventArgs e) 
  {
    this.regionTableAdapter.Fill(
      this.northwindDataSet.Region);
    // resize the column once, but allow the
    // users to change it.
    this.regionDataGridView.AutoResizeColumns(
      DataGridViewAutoSizeColumnsMode.AllCells);
  }
 
  //tracks for PositionChanged event last row
  private DataRow LastDataRow = null;

  /// <SUMMARY>
  /// Checks if there is a row with changes and
  /// writes it to the database
  /// </SUMMARY>
  private void UpdateRowToDatabase() {
    if (LastDataRow!=null) {
      if (LastDataRow.RowState==
          DataRowState.Modified) {
        regionTableAdapter.Update(LastDataRow);
      }
    }
  }
  
  private void regionBindingSource_PositionChanged(
    object sender, EventArgs e) 
  {
    // if the user moves to a new row, check if the 
    // last row was changed
    BindingSource thisBindingSource = 
      (BindingSource)sender;
    DataRow ThisDataRow=
      ((DataRowView)thisBindingSource.Current).Row;
    if (ThisDataRow==LastDataRow) {
      // we need to avoid to write a datarow to the 
      // database when it is still processed. Otherwise
      // we get a problem with the event handling of 
      //the DataTable.
      throw new ApplicationException("It seems the" +
        " PositionChanged event was fired twice for" + 
        " the same row");
    }

    UpdateRowToDatabase();
    // track the current row for next 
    // PositionChanged event
    LastDataRow = ThisDataRow;
  }

  private void MainForm_FormClosed(
    object sender, FormClosedEventArgs e) 
  {
    UpdateRowToDatabase();
  }
}

Like one textbox velue u r passing in database in save click
Synatx :
Dim objNameParam As New SqlParameter("@Name", SqlDbType.varchar)
objNameParam.Direction = ParameterDirection.Input
objNameParam.Value = textbox1.text

same like pass the grid view cell value to database in save click

Syntax :
Dim objNameParamAs New SqlParameter("@Name", SqlDbType.varchar)
objNameParam.Direction = ParameterDirection.Input
objNameParam.Value = DataGridView1.row(0).cell("PassingColumnName").value.ToString()


This is for limited values
i will try write code for multi insert and post it Soon.

Regards
Santosh