I need to validate a name TextBox control so that it is not empty in which an error message will be displayed, and set the focus back to the name's control. I must use a Case Logic that when a city is typed in, the county shows in the Textbox entry. For example "mentor" will be "lake" county. This is for my class, I have read the instructor's examples and read the chapter. I am still having trouble under standing the Case Logic. Here is the code that I have so far. Thanks guys I will even give you reputation and credit for my work. Thanks. How do I get it to pop up the error message if another button is clicked before the name's TextBox is entered?


Public Class Form1

Private Sub PatientTextBox_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles PatientTextBox.TextChanged

If PatientTextBox.TextLength = 0 Then
MessageBox.Show("Please input the patient's name to proceed.", "ErrorMessage")
ElseIf PatientTextBox.Text = "" Then
PatientTextBox.Text = PatientTextBox.ToString
End If

End Sub

Private Sub TeenRadioButton_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TeenRadioButton.CheckedChanged
If TeenRadioButton.Checked = True Then
AgeTextBox.Text = "Teenager"
ElseIf YoungAdultRadioButton.Checked = True Then
AgeTextBox.Text = "Young Adult"
End If
End Sub

Private Sub MidAgeRadioButton_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MidAgeRadioButton.CheckedChanged
If MidAgeRadioButton.Checked = True Then
AgeTextBox.Text = "Middle Age Person"
ElseIf SeniorRadioButton.Checked = True Then
AgeTextBox.Text = "Retirement Age"
End If
End Sub

Private Sub CountyTextBox_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CountyTextBox.TextChanged

Select Case CityTextBox.Text
Case "Mentor"

Case "Kirtland"

Case "Painesville"

Case "Euclid"

End Select

Select Case CountyTextBox.Text
Case "Lake"

Case "Lake"

Case "Lake"

Case "Cuyahoga"
End Select

End Sub
End Class

http://en.wikipedia.org/wiki/Switch_...A.2C_VB_Script

I'm not familier with VB to tell you the best way to handle that error sitation, but I'd suggest taking the check you have inside where you handle PatientTextBox.TextChanged, put it in a function, and call it within each Handles block.

Might you not also disable the other controls from being used while PatientTextBox.TextLength = 0, and when PatientTextBox.TextChanged occurs and PatientTextBox.TextLength > 0, enable them? Not forgetting to disable them again if/when PatientTextBox.TextLength = 0 in subsequent PatientTextBox.TextChanged handlings.

If you need the notification before another button is clicked, you can examine the input focus state or handle key/mouse events.
This is deliberately vague, I know. The specific answers are in the MSDN Help entries for CWnd.