title: Update Command in Datagridview to database
body: <p>i've been working so far with my database issue, i can't proceed with a new module for the reason that i can't update my database through datagridview</p>
  
  <p>can somebody check on my codes why i can't update my database in datagridview using a button click?</p>
  
  <p>here's how i had my datagrid content:</p>
  
  <pre><code>Public Sub loaddgvfrm3()
      cmdconn = New SqlConnection
      cmd = New SqlCommand
      cmdconn.ConnectionString = sqlstr
      cmdconn.Open()
      cmd.Connection = cmdconn
      cmd.CommandText = "select  period, VOUCH_AMT, INDIVIDUAL_AMT, check_no, D_MAILED, DIR_NO, who_updated, claim_no,  year_student from tobee.EBD_BILLHISTORY where CLAIM_NO like '" + txtClaimno.Text + "'"
      'cmd.CommandText = "select  a.period, a.VOUCH_AMT, a.INDIVIDUAL_AMT, a.check_no, a.bal_ent, a.D_MAILED, a.DIR_NO from tobee.EBD_BILLHISTORY a left join carlos.claims_waivee b on a.CLAIM_NO = b.claim_no where b.CLAIM_NO like '" + claimno.ToString + "'"
      Dim dt As New DataTable
      'Dim ds As New DataSet
      da = New SqlDataAdapter
      da.SelectCommand = cmd
      da.Fill(dt)
      Me.DataGridView1.DataSource = dt
      Me.DataGridView2.DataSource = dt
      cmdconn.Close()
  End Sub
  </code></pre>
  
  <p>now i want to modify some rows within that datagridview and update changes that i made into database with a buttonclick</p>
  
  <p>here's my button click code:</p>
  
  <pre><code>Private Sub btnSave_Click(sender As Object, e As EventArgs) Handles btnSave.Click
  
  
      Dim connstr As String = "server=midtelephone\sqlexpress; database=testdb; user= sa; password=sa;"
      Dim cmd2 As New SqlCommand
  
      Try
          Using connection As New SqlConnection(connstr)
              connection.Open()
              cmd2.CommandText = "update tobee.EBD_BILLHISTORY set period=@period, vouch_amt=@vouch_amt, individual_amt=@individual_amt, check_no=@check_no, d_mailed=@d_mailed, dir_no=@dir_no, who_updated=@who_updated where claim_no = '" + txtClaimno.Text + "' "
  
              cmd2.Parameters.Add("@period", SqlDbType.Char, 25, "period")
              cmd2.Parameters.Add(New SqlParameter("@vouch_amt", SqlDbType.Decimal) With {.Precision = 18, .Scale = 2}).Value = "vouch_amt"
              cmd.Parameters.Add(New SqlParameter("@individual_amt", SqlDbType.Decimal) With {.Precision = 18, .Scale = 2}).Value = "individual_amt"
  
              cmd2.Parameters.Add("@check_no", SqlDbType.Char, 15, "check_no")
              'cmd2.Parameters.Add("@d_mailed", SqlDbType.DateTime, "d_mailed")
              cmd2.Parameters.Add("@dir_no", SqlDbType.Char, 15, "DIR_NO")
              cmd2.Parameters.Add("@who_updated", SqlDbType.Char, 15, "who_updated")
              cmd2.ExecuteNonQuery()
              connection.Close()
              MsgBox("changes done")
              'MessageBox.Show("Updated Successfully!", "Update", MessageBoxButtons.OK, MessageBoxIcon.Information)
  
          End Using
      Catch ex As Exception
      msgbox(ex.message)
      End Try
  
  End Sub
  </code></pre>
  
  <p>the problem that occur "executenonquery : connection property has not been initialized"
  what could be the problem of mybutton save?(i don't know if im doing things right, did i connect these two "subs" correcty?) if you have any other suggestion on (updating) the changes i made in the datagridview pls. feel free to modify the save button :(</p>