Refreshing DataGridView after Update or Delete

Question

Hi all, I am trying to figure out how to make it so that my DGV automatically refreshes when I click my Update or Delete buttons in my program. I looked at other threads and couldn't figure out what to do specific to my program. Here is my code:

Public Class Form1
    Dim MyConn As DbConn

    Private Sub btnQuery_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnQuery.Click
        Try
            Dim SQL As String = txtSQL.Text
            Dim DT As DataTable = MyConn.GetDataTable(SQL)
            DataGridView1.DataSource = DT

        Catch ex As Exception
            MsgBox("Invalid Query: " & ex.Message)
        End Try
    End Sub

    
    Private Sub load_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles load.Click
        If OpenFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then
            Dim DatabaseName As String = OpenFileDialog1.FileName
            MyConn = New DbConn(DatabaseName)
        End If
        txtSQL.Text = "SELECT * FROM Items"
    End Sub


    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAttributes.Click
        Dim r As DataGridViewRow = DataGridView1.SelectedRows(0)
        lblRestID.Text = r.Cells("RestaurantID").Value.ToString
        lblCatID.Text = r.Cells("CategoryID").Value.ToString
        lblItemID.Text = r.Cells("ItemID").Value.ToString

        If CDbl(lblRestID.Text) = 1 Then
            lblRestName.Text = "McDonald's"
        ElseIf CDbl(lblRestID.Text) = 2 Then
            lblRestName.Text = "Burger King"
        ElseIf CDbl(lblRestID.Text) = 3 Then
            lblRestName.Text = "Wendy's"
        End If

        If CDbl(lblCatID.Text) = 1 Then
            lblCatName.Text = "Entree"
        ElseIf CDbl(lblCatID.Text) = 2 Then
            lblCatName.Text = "Side Order"
        ElseIf CDbl(lblCatID.Text) = 3 Then
            lblCatName.Text = "Salad"
        ElseIf CDbl(lblCatID.Text) = 4 Then
            lblCatName.Text = "Dessert"
        ElseIf CDbl(lblCatID.Text) = 5 Then
            lblCatName.Text = "Breakfast"
        ElseIf CDbl(lblCatID.Text) = 6 Then
            lblCatName.Text = "Beverage"
        End If

        txtItem.Text = r.Cells("ItemName").Value.ToString
        nudPrice.Value = CDec(r.Cells("Price").Value.ToString)
        nudStart.Value = CDec(r.Cells("StartHour").Value.ToString)
        nudEnd.Value = CDec(r.Cells("EndHour").Value.ToString)

    End Sub


    Private Sub btnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click

        Dim SQL As String = "UPDATE Items SET ItemName='" & txtItem.Text & "', "
        SQL &= "Price=" & nudPrice.Value & ", "
        SQL &= "StartHour=" & nudStart.Value & ", "
        SQL &= "EndHour=" & nudEnd.Value & " "
        SQL &= "WHERE ItemID="
        SQL &= lblItemID.Text
        txtSQL.Text = SQL
    End Sub

    Private Sub btnDelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDelete.Click
        Dim SQL As String = "DELETE FROM Items WHERE ItemID="
        SQL &= lblItemID.Text
        txtSQL.Text = SQL
    End Sub
End Class

Right now, it closes my DGV and I have to click Load File again and then Run Query to load the file into the DGV...I just want to have it auto refresh...what code would I write and where would I put it?

Thanks!

Answer 1

Hi,

You can write code in the event handles of save and delete to reload data from database. As this method is inefficient, it is not recommend. You can modify your code to use a DataAdapter to update the database, then the DataGridView can be updated automatically with reload data from database.

Insert/Update/Delete record with DataGridView... Plz Help!!!!

http://social.msdn.microsoft.com/Forums/en-US/winformsapplications/thread/361f9d4c-1912-4f51-8ac1-bb176d559b11

As this forum focus on Windows Workflow Foundation, it is recommend you post a question at Windows Forms forum. Thanks.

---

Leo Tang [MSFT]
MSDN Community Support | Feedback to us
Get or Request Code Sample from Microsoft
Please remember to mark the replies as answers if they help and unmark them if they provide no help.