First of all name your controls (and variables) properly. Button1, Button2,...LabelN is non-descriptive and less readable. Make an effort and give proper names like updateButton, btnSelectData, nameLabel etc.
Second make a habit of closing your connections and embed all non queries witnin SqlTransaction.
Third to answer your question, you can use dataAdapter to update data as well.
string insertCommandText = "your insert (or update) command goes here";
SqlConnection conn = new SqlConnection("someConnectionString");
SqlCommand insertCmd = null;
SqlTransaction trans = null;
try
{
conn.Open();
trans = conn.BeginTransaction();
insertCmd = new SqlCommand(insertCommandText, conn, trans);
SqlDataAdapter da = new SqlDataAdapte();
da.UpdateCommand = insertCmd;
DataTable dt = yourGridView.DataSource as DataTable;
if(dt != null)
{
da.Update(dt);
}
trans.Commit();
}
catch(Exception ex)
{
trans.Rollback();
}
finally
{
if(trans != null)
{
trans.Dispose();
}
if(inserCmd != null)
{
cmd.Dispose();
}
conn.Close();
}
More on Update method
here.