the coding will works if the data type of my primary key is integer.but when i try to change the primary key in string data type i cant delete oe edit. below is my coding for that 2 button that is working.
coding for edit button
` Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
If Me.DataGridView1.Rows.Count > 0 Then
If Me.DataGridView1.SelectedRows.Count > 0 Then
Dim intISBN As String = Me.DataGridView1.SelectedRows(0).Cells("ISBN").Value
If Not cnn.State = ConnectionState.Open Then
cnn.Open()
End If
Dim da As New OleDb.OleDbDataAdapter("SELECT * FROM Book " & _
" WHERE ISBN=" & intISBN, cnn)
Dim dt As New DataTable
da.Fill(dt)
Me.txtISBN.Text = intISBN
Me.txtBookTitle.Text = dt.Rows(0).Item("BookTitle")
Me.txtAuthor.Text = dt.Rows(0).Item("Author")
Me.txtPublisher.Text = dt.Rows(0).Item("Publisher")
Me.txtEdition.Text = dt.Rows(0).Item("Edition")
Me.txtCategory.Text = dt.Rows(0).Item("Category")
Me.txtQuantity.Text = dt.Rows(0).Item("Quantity")
Me.txtBookPrice.Text = dt.Rows(0).Item("BookPrice")
Me.txtLocation.Text = dt.Rows(0).Item("Location")
Me.txtISBN.Tag = intISBN
Me.Button1.Text = "Update"
Me.Button4.Enabled = False
cnn.Close()
End If
End If
End Sub`
coding for delete button
`Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
If Me.DataGridView1.Rows.Count > 0 Then
If Me.DataGridView1.SelectedRows.Count > 0 Then
Dim x As String = Me.DataGridView1.SelectedRows(0).Cells("ISBN").Value
If Not cnn.State = ConnectionState.Open Then
cnn.Open()
End If
Dim cmb As New OleDb.OleDbCommand
cmb.Connection = cnn
cmb.CommandText = "DELETE FROM Book WHERE ISBN=" & x
cmb.ExecuteNonQuery()
Me.RefreshData()
cnn.Close()
End If
End If
End Sub`
if i declare intISBN and x as Interger, the coding will works. but the problem is the book's ISBN contain interger and string, so i have to use string data type for book's ISBN in my access database.
