Error Handling

[lee123]

hello there i was wondering if anybody know how to do this. I have A form that needs some error handling and I don't know how to do this this form is a lessors form for an apartment building when They add a new lessor in the database i don't want them to enter in the same ID that already exist in the form.. I have One Adodc control on the form and two Buttons one is for them to Add and the other is to Save the information that is tied to a database.

could someone suggest a way to do this in the button i have this code:

Private Sub cmdSave_Click()
    Adodc1.Recordset.MoveNext   
End Sub

how do i put an error handle to say when they add an apartment number and if the apartment number already exist then bring a msgbox up that says "This Apartment Number Already Exist, Add A different Apartment Number In.."

lee123

[OuTCasT]

Hey Lee123

You can use a function to check if the apartment number already exists in the database.

Private Function ValidateApartment(ByVal Apartment As String) As Boolean
        Dim sqlCon As SqlConnection = Nothing
        Dim sqlCom As SqlCommand = Nothing
        Dim lookupID As String
 
        lookupID = Nothing
 
        'Check for ApartmentNumber
        If ((Apartment Is Nothing)) Then
            MsgBox("[ValidateApartment] Input Validation of Apartment Failed", MsgBoxStyle.Critical)
            Return False
        End If
        Try
            sqlCon = New SqlConnection("Server=(local);Data Source=.\SQLEXPRESS;Initial Catalog=DB;Integrated Security=True;Pooling=False")
            sqlCon.Open()
 
            'Create sqlCommand to retrieve Apartment
            sqlCom = New SqlCommand("select [ApartmentNumber] from Apartments where [Apartment]=@ApartmentNumber COLLATE SQL_Latin1_General_CP1_CI_AS", sqlCon)
            sqlCom.Parameters.Add("@ApartmentNumber", SqlDbType.VarChar, 25)
            sqlCom.Parameters("@Apartment").Value = txtApartment.Text
 
            lookupID = sqlCom.ExecuteScalar
 
            sqlCom.Dispose()
            sqlCon.Dispose()
        Catch ex As Exception
            sqlCom.Dispose()
            sqlCon.Dispose()
            MsgBox("Apartment NUmber Already Exists Please make another selection", MsgBoxStyle.Information)
        End Try
        If (lookupID Is Nothing) Then
            Return False
        End If
        Return (String.Compare(lookupID.ToUpper, txtApartment.Text.ToUpper, False) = 0)
    End Function

And then call the function when you leave the textbox.

If ValidateApartment(txtApartment.Text) = True Then
            MsgBox("Apartment Number already exists..Please choose another Apartment")
 
        Else
            If ValidateApartment(txtApartment.Text) = False Then
                Exit Sub
            End If
        End If