The Simplest CRUD Operations for Lookup Tables in ASP.NET - Dealing with DML Operations: continued

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The heart of the application is the "save" button.  Let us go through the following code first:

  PrivateSub btnSave_Click(ByVal sender As System.Object, ByVal e
As System.EventArgs) Handles btnSave.Click
        If Not Me.txtDeptno.Enabled Then 'edit mode
            Try
                'update it
                db.SQLExecute("update dept set dname='" &
Me.txtDname.Text & "', loc='" & Me.txtLocation.Text & "' where
deptno=" & Me.txtDeptno.Text)
            Catch ex As Exception 'any other error
                Me.lblMsg.Text = ex.Message
                Me.lblMsg.Visible = True
                Exit Sub
            End Try
        Else 'add new mode
            'validation for unique deptno
            If db.getRowValue("select 'exists' from dept where
deptno=" & Me.txtDeptno.Text) = "exists" Then
                Me.lblMsg.Text = "Dept already exists"
                Me.lblMsg.Visible = True
                Exit Sub
            End If
            'proceeding to insert
            Try
                db.SQLExecute("insert into dept
(deptno,dname,loc) values (" & Me.txtDeptno.Text & ",'" &
Me.txtDname.Text & "','" & Me.txtLocation.Text & "')")
            Catch ex As Exception 'any other error
                Me.lblMsg.Text = ex.Message
                Me.lblMsg.Visible = True
                Exit Sub
            End Try
        End If
        'after successfully saving...update the grid
        Me.frDept.Visible = False
        BindGrid()
    End Sub

The above method simply separates every operation for ease in understanding.  Each case works with a separate DML option.  The above includes validation along with the operations.

Next: Points to note >>
 

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Comments On: The Simplest CRUD Operations for Lookup Tables in ASP.NET

· why wouldn't you use a tableadapter?or the MS Enterprise Library?    · ofcourse, I would have used. But, I didn't mean to use enterprise library in this...   >>> Post your comment now!