Looking for a better way to evaluate textbox controls

[FastEddie]

I have multiple textboxes that should have numeric values and others that need to have some kind of entry added. So far I have been doing it this way but I am wondering if there is a better way. How would you do this?

Dim strAction As String = txtAction.Text
        Select Case strAction
            Case "A"
                If IsNumeric(txtEmp.Text) = False Then
                    MsgBox("Employee number must be a numeric value.", _
                          MsgBoxStyle.OKOnly, "Employee Number Error")
                    txtEmp.Focus()
                    Exit Sub
                End If
                If IsNumeric(txtDayCode.Text) = False Then
                    MsgBox("This field must be a numeric value 1-7.", _
                        MsgBoxStyle.OKOnly, "Day Code Error")
                    txtDayCode.Focus()
                    Exit Sub
                End If
                If (txtJobNumber.Text) = "" Then
                    MsgBox("The job number field can not be left blank.")
                    txtJobNumber.Focus()
                    Exit Sub
                End If
                If (txtPC.Text) = "" Then
                    MsgBox("The Pc Field can not be left blank.")
                    txtPC.Focus()
                    Exit Sub
                End If
                If (txtTime.Text) = "" Then
                    MsgBox("The time field can not be left blank.")
                    txtTime.Focus()
                    Exit Sub
                End If
                If (txtAmount.Text) = "" Then
                    MsgBox("The amount field can not be left blank.")
                    txtAmount.Focus()
                    Exit Sub
                End If