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checking if sqldataadaptor is empty

Posted By:      Posted Date: October 19, 2010    Points: 0   Category :ASP.Net

hi guys,

i'm trying to create a program that can view review in a collapsiblePanel. the data will be placed in a gridview that is inside the collapsible panel. my problem is that when there is no review data at the database, i want to display an error message inside the collapsible panel. however, the code that i have been trying doesn't seem to be able to read if the sqldataadaptor is empty or not. below is my code

Public Sub getGridList()
        Dim tourId As String = lblTourId.Text

        Dim strConn As String = ConfigurationManager.ConnectionStrings("ProrsumDBConnectionString").ConnectionString
        'create sql connection
        Dim myConn As New SqlConnection(strConn)
        Dim myAdp As SqlDataAdapter
        'Open connection; Note: You need to open a connection to database

            Dim cmd As String = "SELECT reviewID, " & _
                                    " comments, " & _
                                    " reviewDate " & _
                                " FROM Review" & _
                                " WHERE tourID = '" + tourId + "'"
            myAdp = New SqlDataAdapter(cmd, myConn)

            ds = New DataSet


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