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

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I included a button with the caption "Add."  Actually, it does nothing other than clear the values existing in all the controls.  Let us go through the following code:

  PrivateSub btnAdd_Click(ByVal sender As System.Object, ByVal e
As System.EventArgs) Handles btnAdd.Click
        Me.txtDeptno.Text = ""
        Me.txtDname.Text = ""
        Me.txtLocation.Text = ""
        Me.txtDeptno.Enabled = True
        Me.frDept.Visible = True
    End Sub

The above simply clears all controls and makes the "editing layout" visible so that you can enter a new record.  When the user clicks on "edit" on the datagrid, it will invoke the following method:

  PrivateSub ShowEdit(ByVal DeptID As String)
        Dim dr As DataRow = db.getDataRow("select * from dept
where deptno=" & DeptID)
        If dr Is Nothing Then
            Me.lblMsg.Text = "Dept Not found"
            Me.lblMsg.Visible = True
            Exit Sub
        End If
        Me.txtDeptno.Text = dr("Deptno")
        Me.txtDeptno.Enabled = False
        Me.txtDname.Text = dr("Dname")
        Me.txtLocation.Text = dr("Loc")
        Me.frDept.Visible = True
    End Sub

You can understand that the above simply retrieves a record from the database and displays the same on the screen.  The button "Cancel" is provided with the following code:

  PrivateSub btnCancel_Click(ByVal sender As System.Object, ByVal
e As System.EventArgs) Handles btnCancel.Click
        Me.frDept.Visible = False
        Me.lblMsg.Visible = False
    End Sub

The above method simply hides the "editing layout" and existing error messages.

Next: Dealing with DML Operations: continued >>
 

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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!