The Simplest CRUD Operations for Lookup Tables in ASP.NET - Retrieving information from the database

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To retrieve information from the database onto the grid, you try to define a simple method something like the following:

  PrivateSub BindGrid()
        Me.DataGrid1.DataSource = db.getDataTable("select * from
dept")
        Me.DataGrid1.DataBind()
    End Sub

The above would simply retrieve all of the information from the table "dept" and assign it to "datagrid."  When any button in the datagrid is hit, it must execute the respective method. The following code will do that based on the definitions of the columns you added to the datagrid (please refer to the first section).

  PrivateSub DataGrid1_ItemCommand(ByVal source As Object, ByVal
e As System.Web.UI.WebControls.DataGridCommandEventArgs) Handles
DataGrid1.ItemCommand
        Dim DeptId As String = e.Item.Cells(2).Text
        Select Case e.CommandName
            Case "OnEdit"
                ShowEdit(DeptId)
            Case "OnDel"
                Delete(DeptId)
        End Select
    End Sub

When you click on "edit" or "delete," you must find the "departmentID" present in the row on which the user clicked.  The following statement would give you the same:

        Dim DeptId As String = e.Item.Cells(2).Text

You must make sure that the "CommandName" you specify in the above code matches with the columns defined earlier.

Next: Dealing with DML operations >>
 

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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!