VBA 6 + how to export variable to click button - visual-studio

I created the following VB6 code and I created two controls on my form - Combo1 (listbox) and Command3 (a button).
When I select an item from the Combo1 list I assign a string to the form scoped variable param and display it in a message box and then dismiss it.
But when I then click on the Command3 button and try to display the same param variable in a message box then there is no value stored.
Here's my code:
Dim param As String
Sub Form_load()
Combo1.AddItem "linux ver"
Combo1.AddItem "linux ver"
End Sub
Sub Combo1_Click()
If Combo1.ListIndex = 0 Then
param = "linux 5.1"
MsgBox param
End If
If Combo1.ListIndex = 1 Then
param = "linux 5.5"
MsgBox param
End If
End Sub
Sub Command3_Click()
MsgBox "param" & param
End Sub
What am I doing wrong?

It looks like this is due to Variable Scope. You need to define "param" outside of the Combo1_Click() subroutine, because as it stands, param only exists and is accessible within that routine.

What if Combo1.ListIndex is -1? Or 2?
Your param variable would never be assigned, and the behavior you see is exactly what is expected.

Related

Why does my global Dictionary variable not properly set in VBScript?

I am using ASP Classic with VBScript, and I have been trying to create a Dictionary, populate it, then have it accessible globally. The way my page is set up, I have a main Class for one of my Objects, that has multiple Display subs, and changing a "displaymode" hidden input causes the page to submit and reload a new page depending on which displaymode matches which display sub. It has worked well for everything so far, but I cannot figure out how to assign a Dictionary globally.
I have the Dictionary variable declared and set globally, then in one sub I call another sub to assign it. I can then use the Dictionary perfectly fine inside both subs, but when I try to use it in anything else outside those subs, it is empty. Here is an example:
Dim dict
Set dict = CreateObject("Scripting.Dictionary")
DisplayObj
Sub DisplayObj()
Dim example
Set example = New exampleClass
With example
.Display
End With
End Sub
Class exampleClass
Public Sub Display()
Select Case Request("Display Mode")
Case "displayFull"
DisplayFull
Case "displaySingle"
DisplaySingle
End Select
End Sub
Public Sub DisplayFull()
SetList()
response.write ""& dict(0) &""
End Sub
Public Sub SetList()
dict.Add 0, "hello"
End Sub
Public Sub DisplaySingle()
response.write ""& dict(0) &""
End Sub
End Class
So when the page is set to displayFull and the DisplayFull sub is called, the dict variable is set properly and displays "hello". I have a click event change the display mode to DisplaySingle, and when that loads it displays nothing, and says the dict variable is empty. How can I have the SetList sub set the Dictionary globally?

Is there a built in MS Access VBA Event to simplify Data Verification and SetFocus

Bit of a rookie issue here. How do you deal with data verification using Access Events? The problem is that when I use SetFocus to return the Cursor to the field with the errant data, Access goes through the _Exit and/or _LostFocus Events of the next Control in the Tab Order. If those include data validation procedures, the desired SetFocus is circumvented.
Using techturtles answer, I came up with this "solution" (read "hack").
Private Sub ServicingEmployee_LostFocus() 'Check data validity
If dataEntryCancelled Then Exit Sub
Dim cntrl As Control
Set cntrl = Me.ServicingEmployee
Dim myResponse As Integer
If IsNull(cntrl.Value) Then
myResponse = MsgBox("This field cannot be left blank.", vbOKOnly, "Enter Date Collected")
dataErrorInPreviousField = True
**'Next line sets a Public Control**
Set controlWithDataEntryError = Me.ServicingEmployee
End If
End Sub
Private Sub Client_GotFocus() '**Check for data Error in previous Control according to Tab Order**
If dataErrorInPreviousField Then Call dataErrorProc
End Sub
Public Sub dataErrorProc()
With controlWithDataEntryError
.SetFocus
.SelStart = 0
.SelLength = Len(.Text)
End With
dataErrorInPreviousField = False
End Sub
Private Sub Client_Exit(Cancel As Integer) '**Example of Bypassing _Exit Event**
If dataEntryCancelled Or dataErrorInPreviousField Then Exit Sub
.
...
End Sub
My question is this: Is there a simpler way to accomplish this?
First, I would strongly encourage you to add table constraints in addition to your form validation, if you haven't already done so. Assuming this form is tied to a table in Access, just make sure the ServicingEmployee field (in the table) is set to required. That way, you have another level of validation making sure the field has a value.
For form validation, you can use either the form's or control's BeforeUpdate event. If you use the form's event, you only have to run the check once.
I would also suggest having a separate function (within the form) to check validity. Something like this (here, I'm using a form tied to an Employees table, with a first name and last field which should both be non-null):
Private Function isFormValid() As Boolean
' we start off assuming form is valid
isFormValid = True
If IsNull(Me.txtFirstName) Then
MsgBox "First name cannot be blank", vbOKOnly
Me.txtFirstName.SetFocus
isFormValid = False
ElseIf IsNull(Me.txtLastName) Then
MsgBox "Last name cannot be blank", vbOKOnly
Me.txtLastName.SetFocus
isFormValid = False
End If
End Function
Private Sub Form_BeforeUpdate(Cancel As Integer)
If Not isFormValid Then
Cancel = 1
End If
End Sub

For Loop gives Object Required Error

I am comparatively new to UFT as well as VB script.
I am trying to check innertext of divs inside For loop.
set getData = Browser("Browser").Page("Page").Object.getElementsByClassName("ClassName")
'Below line outputs 5'
msgbox getData.length-1
'output innertext for all these divs'
For i=0 to getData.length-1
msgbox getData(i).innertext
Next
This gives me Object Required Error on this line
msgbox getData(i).innertext
My first and 2nd element is blank while 3,4,5 are non-empty values.
When I write
msgbox getData(0).innertext
msgbox getData(1).innertext
msgbox getData(2).innertext
It gives me proper results
I further need to check this data against "Data" spreadsheet in UFT
Any pointers would be very much helpful.
Thanks,
Clarification needed:
As you would like to query div text, Is that any reason to use ClassName? If that so, you could use getElementsbyTagName instead getElementsByClassName.
However, I enhanced the code and adapting the query by any tag name option in the function. Here you go.
Dim objResultsDictionary
Set objResultsDictionary = GetTextContentFromHtmlTag(Browser("title:=Welcome: Mercury Tours").Page("title:=.*"),"div","")
Msgbox objResultsDictionary.Count
Result:8
Set objResultsDictionary = GetTextContentFromHtmlTag(Browser("title:=Welcome: Mercury Tours").Page("title:=.*"),"ClassName","mouseOut")
Msgbox objResultsDictionary.Count
Result = 11
Public Function GetTextContentFromHtmlTag(ByVal BrowserObject,ByVal TagName,ByVal TagValue)
Dim objDictionary
Dim objCollection
Set objDictionary = CreateObject("Scripting.Dictionary")
Select Case UCase(TagName)
Case "DIV"
Set objCollection = BrowserObject.Object.getElementsByTagName(TagName)
Case "CLASSNAME"
Set objCollection = BrowserObject.Object.getElementsByClassName(TagValue)
End Select
intDivCount = objCollection.Length
If intDivCount > 0 Then
For intCounter = 0 To intDivCount
If IsObject(objCollection(intCounter)) Then
strTagInnerText = objCollection(intCounter).innerText
If strTagInnerText <> "" Then
objDictionary.Add intCounter,strTagInnerText
End If
End If
Next
End If
Set GetTextContentFromHtmlTag = objDictionary
End Function
What you have to do:
You have to iterate the dictionary and get the innertext of the each tag.
Its giving you that error most probably because, there is various elements with the same class name other than the div or divs.
Try using some other properties.

How to pass value to SQL Query in Data Environment's Command Object at run-time in Visual Basic 6.0?

In DataEnvironment I have a Command Object in which I have
given following SQL Query:
SELECT * FROM userdetails WHERE Date = Todays_date
Here Todays_date is a public variable in Module.
This variable accepts value at run-time.
How to call variable in DataEnvironment's SQL Query?
The VB6 manuals cover this in Closing and Reopening the Recordset under the heading Data Environment Programming Guidelines. The example given there looks like:
Option Explicit
Private Sub Command1_Click()
' You must close the recordset before changing the parameter.
If DataEnvironment1.rsCommandQuery.State = adStateOpen Then
DataEnvironment1.rsCommandQuery.Close
End If
' Reopen the recordset with the input parameter supplied by
' the TextBox control.
DataEnvironment1.CommandQuery Text1.Text
With Text2
.DataField = "AU_LName"
.DataMember = "CommandQuery"
Set .DataSource = DataEnvironment1
End With
End Sub
Private Sub Form_Load()
' Supply a default value.
Text1.Text = "172-32-1172"
' Change the CommandButton caption.
Command1.Caption = "Run Query"
End Sub
You call the Command object as a method of its parent DataEnvironment, passing the parameters there. Gotta love The Fine Manual.

How to gracefully exit from the middle of a nested subroutine when user cancels?

(I'm using VB6 but I imagine this comes up in most other languages.)
I've got a GUI button that calls a routine that takes a minute or two to complete. I want impatient users to be able to click on the button a second time to have it gracefully exit out of the routine at any point.
I used a static variable to make this work pretty well (see code below), but I'm cleaning up the project and I want to put the For/Next loop into its own function, since it's required in several different places in the project.
But doing that would break my static flag embedded in the for/next, so I need to make some changes. Before I do something hare-brained with public (global) variables, I thought I'd ask what other (smarter, perhaps actually CS educated) people have done when faced with this problem.
So basically my question is how do I replicate this:
Private Sub DoSomething_Click()
Static ExitThisSub As Boolean ' Needed for graceful exit
If DoSomething.Caption = "Click To Stop Doing Something" Then
ExitThisSub = False ' this is the first time we've entered this sub
Else ' We've re-entered this routine (user clicked on button to stop it)
ExitThisSub = True ' Set this so we'll see it when we exit this re-entry
Exit Sub '
End If
DoSomething.Caption = "Click To Stop Doing Something"
For i = 0 To ReallyBigNumber
Call DoingSomethingSomewhatTimeConsuming
If ExitThisSub = True Then GoTo ExitThisSubNow
DoEvents
Next
' The next line was missing from my original example,
' prompting appropriate comments
DoSomething.Caption = "Click To Do Something"
Exit Sub
ExitThisSubNow:
ExitThisSub = False ' clear this so we can reenter later
DoSomething.Caption = "Click To Do Something"
End Sub
When I move the for/next loop to its own function?
I'm thinking I'll change ExitThisSub to a public variable QuitDoingSoManyLongCalculations that will exit the new for/next sub and then the DoSomething_Click in the same way.
But I always feel like an amateur (which I am) when I use global variables - is there a more elegant solution?
Well you could declare the variable at module level in the forms as private.
That is not a global but a module level variable.
Then you could pass it to the function you create and check it in the function.
But be careful with the DoEvents. It basically means allow the windows message loop to process messages. This means that not only can the user click your button again, they can close the form and do other things. So when you are in this loop you'll need to set a module level variable anyway as you'll need to check for it in a QueryUnload of the form and in any event handlers.
You can also use the Tag property of the control itself to store a flag of sorts. But I don't consider that more elegant.
I also prefer to use two different buttons. Just hide one and show the other. That way your cancel code and run code are separated in different event handlers.
To expand on my answer here is some sample code that handles the unloading aspect.
Here if you stop via the x it prompts you. If you kill via task manager, it dies gracefully.
Option Explicit
Private Enum StopFlag
NotSet = 0
StopNow = 1
StopExit = 2
End Enum
Private m_lngStopFlag As StopFlag
Private m_blnProcessing As Boolean
Private Sub cmdGo_Click()
Dim lngIndex As Long
Dim strTemp As String
m_lngStopFlag = StopFlag.NotSet
m_blnProcessing = True
cmdStop.Visible = True
cmdGo.Visible = False
For lngIndex = 1 To 99999999
' check stop flag
Select Case m_lngStopFlag
Case StopFlag.StopNow
MsgBox "Stopping - Last Number Was " & strTemp
Exit For
Case StopFlag.StopExit
m_blnProcessing = False
End
End Select
' do your processing
strTemp = CStr(lngIndex)
' let message loop process messages
DoEvents
Next lngIndex
m_lngStopFlag = StopFlag.NotSet
m_blnProcessing = False
cmdGo.Visible = True
cmdStop.Visible = False
End Sub
Private Sub cmdStop_Click()
m_lngStopFlag = StopFlag.StopNow
End Sub
Private Sub Form_Load()
m_blnProcessing = False
End Sub
Private Sub Form_QueryUnload(Cancel As Integer, UnloadMode As Integer)
Select Case UnloadMode
Case vbFormControlMenu, vbFormCode
If m_blnProcessing Then
Cancel = True
If MsgBox("Unload Attempted - Cancel Running Process?", vbOKCancel + vbDefaultButton1 + vbQuestion, "Test") = vbOK Then
m_lngStopFlag = StopFlag.StopExit
End If
End If
Case Else
m_lngStopFlag = StopFlag.StopExit
Cancel = True
End Select
End Sub
You need some kind of shared variable so that your for loop and your button can communicate. I'd put the for loop (and its associated code) in a command object. My VB is rusty but I think you can declare Modules with their own 'global' variables and functions. You can move all the code into a module and just check the global variable as you do now.
My main concern with the code sample you've posted has nothing to do with user-cancelling but rather everything else: you check your running state by reading the button text instead of doing that the other way around (set the button text because of the running state, which should be stored in a variable); you use a GOTO to exit your for loop instead of a break (does VB have breaks?) and you put your cleanup code outside the normal flow, when it seems to me that it could be run regardless of whether the user cancelled or not.
One possible alternative is to offload your heavy-work function to a new Thread. Then you can either directly kill that thread if the user wants to cancel, or you can send a message to the thread.
Toggling via button name, as you are doing above, is a pretty commonly seen trick though, and pretty safe if you only have a couple of button states.
I've always used a global boolean variable like bUserPressedCancel, along with DoEvents within a loop. Elegant, smelegant, it works.
I agree with Mr Shiny that testing against the value of a caption is not a great idea. If you change the text on the button in the designer, you'll break the code. Better not to rely on the wording of the text for your code to work.
Works until you need to do localization or any other thing else that require the UI to be changed independently of the logic. I would use the Tag property or a private module level variable . Then you can vary the caption independently from the logic.
If it was me I'd use 2 buttons - one to GO and one to STOP. The STOP button is made visible when you click GO. The Click event for STOP simply hides itself - that's it.
Your loop can then simply check to see if the STOP button is still visible. If it's not, that means it was clicked and you should break out.
Your controls are static objects with form scope...

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