C4.3, 4 Lab: Conditionals - Select Statement and Additional Input Controls Solutions

Transcription

1 C4.3, 4 Lab: Conditionals - Select Statement and Additional Input Controls Solutions Between the comments included with the code and the code itself, you shouldn t have any problems understanding what s going on. 1. frmc Public Class frmc4_3_24 Private Sub btnstart_click(byval sender As System.Object, ByVal e As System.EventArgs) Handles btnstart.click Dim callnumber As Integer Dim location As String callnumber = CStr(txtInput.Text) Select callnumber Case 100 To 199 location = "basement" Case 200 To 500 location = "main floor" Case Is > 900 location = "main floor" Case 501 To 699 location = "upper floor" Case 751 To 900 location = "upper floor" Case 700 To 750 location = "archives" Case Else location = "INVALID CALL NUMBER: LESS THAN 100" End Select lstoutput.items.add(location) 1

2 2. frmc Public Class frmc4_3_30 Private Sub btnstart_click(byval sender As System.Object, ByVal e As System.EventArgs) Handles btnstart.click Dim s As String Dim meaning As String s = txtinput.text s = s.tolower So don t have to check upper case Select Case s Case "ac" meaning = "before meals" Case "ad lib" meaning = "freely as needed" Case "bid" meaning = "twice daily" Case "gtt" meaning = "a drop" Case "hs" meaning = "at bedtime" Case "quid" meaning = "four times a day" Case Else meaning = "UNKNOWN ABBREVIATION" End Select lstoutput.items.add(meaning) 2

3 3. frmc Public Class frmc4_4_18 Private Sub btnbookflight_click(byval sender As System.Object, ByVal e As System.EventArgs) Handles btnbookflight.click Dim destination As String Dim departure As String Dim output As String Get rid of old results destination = lstto.selecteditem departure = lstfrom.selecteditem If destination = Nothing Or departure = Nothing Then MessageBox.Show("You must select both a TO and FROM airport") ElseIf destination = departure Then MessageBox.Show("TO and FROM locations cannot be the same") Else output = "You are flying from " & departure & " to " & destination lstoutput.items.add(output) lstto.selecteditem = Nothing Erase last selections lstfrom.selecteditem = Nothing Load event handlers are executed before the program runs Rather than add the to and from locations in the design window I m adding them in the program itself so it s obvious what they are without going to the list box properties Private Sub frmc4_4_18_load(byval sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load lstfrom.items.add("aus") lstfrom.items.add("bos") lstfrom.items.add("bwi") lstfrom.items.add("dfw") lstfrom.items.add("jfk") lstfrom.items.add("lax") lstfrom.items.add("mia") lstfrom.items.add("ord") lstfrom.items.add("sfo") lstto.items.add("aus") lstto.items.add("bos") lstto.items.add("bwi") lstto.items.add("dfw") lstto.items.add("jfk") lstto.items.add("lax") lstto.items.add("mia") lstto.items.add("ord") lstto.items.add("sfo") 3

4 4. frmc Public Class frmc4_4_24 Private Sub btnapplycolors_click(byval sender As System.Object, ByVal e As System.EventArgs) Handles btnapplycolors.click Dim foreground As String Dim background As String If radwhitef.checked Then Store colors in variables for comparison foreground = radwhitef.text foreground = radyellowf.text foreground = radredf.text foreground = radbluef.text background = radwhitef.text background = radyellowf.text background = radredf.text background = radbluef.text If background = Nothing Or foreground = Nothing Then MessageBox.Show("MUST CHECK BOTH FOREGROUND AND BACKGROUND COLOR") ElseIf background.equals(foreground) Then MessageBox.Show("CANNOT HAVE SAME FOREGROUND AND BACKGROUND COLORS") Else If get to here everything is OK. If radwhitef.checked Then Could use the variables background and foreground instead lbldisplay.forecolor = Color.White lbldisplay.forecolor = Color.Yellow lbldisplay.forecolor = Color.Red lbldisplay.forecolor = Color.Blue lbldisplay.backcolor = Color.White lbldisplay.backcolor = Color.Yellow lbldisplay.backcolor = Color.Red lbldisplay.backcolor = Color.Blue This set of ifs uncheck all radio buttons. Not really necessary If radwhitef.checked Then radwhitef.checked = False radyellowf.checked = False 4

5 radredf.checked = False radbluef.checked = False radwhiteb.checked = False radyellowb.checked = False radredb.checked = False radblueb.checked = False 5