Hints and Recipes for VB6: Difference between revisions

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   End With
   End With
   cboDelimiter = "TAB"
   cboDelimiter = "TAB"
== Write/Create a new file using FileSystemObject ==
*must add 'reference' to "Microsoft Scripting Runtime"
  Dim fso As New FileSystemObject, fsoStream As TextStream
  Dim rec1, strLine, strFileSpec
  Dim cnt0 As Integer, tag1 As Integer
  strFileSpec = Environ("HOMEPATH") & "\My Documents\kaching.log"
  strLine = "kaching incident " & Date & " " & Format(time, "HH:mm:ss") & vbCrLf
  Set fsoStream = fso.CreateTextFile(strFileSpec, True)
  fsoStream.Write strLine
  fsoStream.Close
  Set fsoStream = Nothing: Set fso = Nothing
== Write if exists, create if doesn't exist using FileSystemObject ==
  If fso.FileExists(strFileSpec) Then
    Set fsoStream = fso.OpenTextFile(strFileSpec, 2)
  Else
    Set fsoStream = fso.CreateTextFile(strFileSpec, True)
  End If
 
  fsoStream.Write strLine
  fsoStream.Close
  Set fsoStream = Nothing: Set fso = Nothing
  ' strFileSpec, 1 : ForReading 2 : ForWriting  8 : ForAppending 
== Write to control on another form and display ==
  Dim lblCaught As Label
  Set lblCaught = frmKaching.lblCaught
  frmKaching.WindowState = vbNormal
  lblCaught = "You've Been Naughty!"
  frmKaching.Show


== Delay without using a Timer control ==
== Delay without using a Timer control ==
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     Loop
     Loop
   End Sub
   End Sub
== Determine is a form has been loaded ==
The wrong way:
  if form1.visible = true then
The reason:
Due to the way an intrinsic variable instance works in VB, the line above will actually cause form1 to load.  Forms are loaded automatically whenever referenced in code, whether loaded visibly or not.
Special thanks to a gentleman named Steve Gerrard who posted a correct sample script on another forum.  His example works by going through a list of loaded forms and matching by the form name you are looking for.
  Public Function FormIsLoaded(FormName As String) As Boolean
    Dim oFrm As Form
    For Each oFrm In Forms
      If oFrm.Name = FormName Then
        FormIsLoaded = True
        Exit For
      End If
    Next oFrm
  End Function
lovely!


== Quickly determine which option button is selected ==
== Quickly determine which option button is selected ==

Revision as of 10:01, 2 February 2008

Date and Time examples with formatting options

 strTimeStamp = Date & " " & Format(Time, "HH:mm:ss")
 strMsg = strMsg & "date/time of request: " & Date & " " & Time & vbCrLf
 strSQLdate = Format(Date, "M/d/yyyy")

Combobox

 With cboDelimiter
   .AddItem "TAB"
   .AddItem "PIPE"
   .AddItem "SPACE"
   .AddItem "fancy!"
 End With
 cboDelimiter = "TAB"

Delay without using a Timer control

 Public Sub LongDelay(intSeconds As Long)
   Dim cnt As Double
   cnt = Timer + intSeconds
   Do While Timer < cnt
     DoEvents
   Loop
 End Sub

Quickly determine which option button is selected

Often OptionButton controls are arranged in control arrays. To quickly find the index of the only selected OptionButton control apply this little math trick. The following example assumes there are 3 option buttons in a control array. 

intSelected = Option(0).Value * 0 - Option(1).Value * 1 - Option(2).Value * 2

Note that the first operand is always zero, and you can simplify the above expression as follows: 

intSelected = -Option(1).Value - Option(2).Value * 2

Credit to Ed Lampman for this VB trick.

 

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