Newbie: Dynamic Variable Names

[JBuckland]

Im trying to create a 7 segment display for a project in visual basic 2005 express edition. I have a 2 dimentional boolean which stores the values of each of the segments for a certain display. I have written a case statement for the first display and would like to use it for the other displays instead of having to copy the code. I have tried everything I can think of but can't get it to pass the name of the boolean array im trying to set the values to from my main code to the procedure. Here is the code im passing:

 For i As Integer = 1 To Len(CStr(Number)) Step 1  
Dim MidString As String              
MidString = CStr(Number)              
[B][U]GetValues("VisPPL", Mid(MidString, (Len(MidString) - i + 1), 1), i)[/U][/B]         
Next i

The "VisPPL" is the name of the boolean array im trying to set the values to.

Here is the code from the start of my procedure my procedure:

Public Sub GetValues(ByVal VarName As [B][U]????[/U][/B], ByVal Number As Integer, ByVal Row As Integer)   
           
Select Case Number 
             
Case 0                  
VarName(Row, 1) = True                  
VarName(Row, 2) = True                 
VarName(Row, 3) = True                  
VarName(Row, 4) = False                  
VarName(Row, 5) = True                  
VarName(Row, 6) = True                  
VarName(Row, 7) = True

Ive tried using a string where the ???? is as the datatype for the name of the boolean array and im simply trying to get the VarName to be replaced with my boolean name (VisPPL) which im passing to it so I can pass different boolean arrays to the same procedure and it will set the values to that array.

Im not sure if I have explained my problem very well but any help is greatly appreciated.

Thanks, James

[kadghar]

...

Public Sub GetValues(ByVal VarName As [B][U]????[/U][/B], ByVal Number As Integer, ByVal Row As Integer)   
           
Select Case Number 
             
Case 0                  
VarName(Row, 1) = True                  
VarName(Row, 2) = True                 
VarName(Row, 3) = True                  
VarName(Row, 4) = False                  
VarName(Row, 5) = True                  
VarName(Row, 6) = True                  
VarName(Row, 7) = True

Use ByRef, instead of ByVal, i'd say something like this will do

[CODE=vb]Public Sub GetValues(ByRef VarName, ByVal Number As Integer, ByVal Row As Integer)
dim i as integer
select case number
case 0
for i = 1 to 7
varname(row,i)= true
next
varname(row,4)= false
case 1
....[/CODE]

This way, the variable will be called VarName inside the sub, but as you change VarName, you'll be changing the reference too.

HTH

[JBuckland]

Thanks that worked great. I have another question, at the moment I have to declare the values of each of my segments in reference to the array in the follow way:

        ltrTop1.Visible = Segs(2, 3, 1)
        ltrTopL1.Visible = Segs(2, 3, 2)
        ltrTopR1.Visible = Segs(2, 3, 3)
        ltrMid1.Visible = Segs(2, 3, 4)
        ltrBotL1.Visible = Segs(2, 3, 5)
        ltrBotR1.Visible = Segs(2, 3, 6)
        ltrBot1.Visible = Segs(2, 3, 7)

        ltrTop2.Visible = Segs(2, 2, 1)
        ltrTopL2.Visible = Segs(2, 2, 2)
        ltrTopR2.Visible = Segs(2, 2, 3)
        ltrMid2.Visible = Segs(2, 2, 4)
        ltrBotL2.Visible = Segs(2, 2, 5)
        ltrBotR2.Visible = Segs(2, 2, 6)
        ltrBot2.Visible = Segs(2, 2, 7)

        ltrTop3.Visible = Segs(2, 1, 1)
        ltrTopL3.Visible = Segs(2, 1, 2)
        ltrTopR3.Visible = Segs(2, 1, 3)
        ltrMid3.Visible = Segs(2, 1, 4)
        ltrBotL3.Visible = Segs(2, 1, 5)
        ltrBotR3.Visible = Segs(2, 1, 6)
        ltrBot3.Visible = Segs(2, 1, 7)

I was hoping to change this to something more like

For i As integer = 1 to 3 Step 1

        ltrTop"i".Visible = Segs(2, (4 - "i"), 1)
        ltrTopL"i".Visible = Segs(2, (4 - "i"), 2)
        ltrTopR"i".Visible = Segs(2, (4 - "i"), 3)
        ltrMid"i".Visible = Segs(2, (4 - "i"), 4)
        ltrBotL"i".Visible = Segs(2, (4 - "i"), 5)
        ltrBotR"i".Visible = Segs(2, (4 - "i"), 6)
        ltrBot"i".Visible = Segs(2, (4 - "i"), 7)

Next

But, I cannot get it to work. Once again thanks for all the help its greatly appreciated. I have been racking my brains on how to tackle this 7 segment display and I just feel there should be a simpler way to go about things but I cannot think of one, it doesn't help that i'm new to visual basic with a background in PHP which i thought would help but its proving not so.

Thanks, James

[kadghar]

...
I was hoping to change this to something more like

For i As integer = 1 to 3 Step 1

        ltrTop"i".Visible = Segs(2, (4 - "i"), 1)
        ltrTopL"i".Visible = Segs(2, (4 - "i"), 2)
        ltrTopR"i".Visible = Segs(2, (4 - "i"), 3)
        ltrMid"i".Visible = Segs(2, (4 - "i"), 4)
        ltrBotL"i".Visible = Segs(2, (4 - "i"), 5)
        ltrBotR"i".Visible = Segs(2, (4 - "i"), 6)
        ltrBot"i".Visible = Segs(2, (4 - "i"), 7)

Next

Thanks, James

No, in VB you cannot do that with the names of the objects. But if they're controls in a Form, you can call them from the controls collection, using their name as a string.

Lets say you have your form called Form1, then something like this will do:

[CODE=vb]dim i as integer
For i = 1 to 3
form1.controls( "ltrTop" & i).visible = segs(2, 4-i , 1)
form1.controls( "ltrTopL" & i).visible = segs(2, 4-i,2)
'... and so on
next[/CODE]

HTH

[JBuckland]

Thanks, I have it set up like this but im still getting an error:

For i3 As Integer = 1 To 5 Step 1
            Me.Controls("salTop" & i3).Visible = Segs(3, (6 - i3), 1)
            Me.Controls("salTopL" & i3).Visible = Segs(3, (6 - i3), 2)
            Me.Controls("salTopR" & i3).Visible = Segs(3, (6 - i3), 3)
            Me.Controls("salMid" & i3).Visible = Segs(3, (6 - i3), 4)
            Me.Controls("salBotL" & i3).Visible = Segs(3, (6 - i3), 5)
            Me.Controls("salBotR" & i3).Visible = Segs(3, (6 - i3), 6)
            Me.Controls("salBot" & i3).Visible = Segs(3, (6 - i3), 7)
        Next i3

        For i2 As Integer = 1 To 5 Step 1
            Me.Controls("ltrTop" & i2).Visible = Segs(2, (4 - i2), 1)
            Me.Controls("ltrTopL" & i2).Visible = Segs(2, (4 - i2), 2)
            Me.Controls("ltrTopR" & i2).Visible = Segs(2, (4 - i2), 3)
            Me.Controls("ltrMid" & i2).Visible = Segs(2, (4 - i2), 4)
            Me.Controls("ltrBotL" & i2).Visible = Segs(2, (4 - i2), 5)
            Me.Controls("ltrBotR" & i2).Visible = Segs(2, (4 - i2), 6)
            Me.Controls("ltrBot" & i2).Visible = Segs(2, (4 - i2), 7)
        Next i2


        For i As Integer = 1 To 5 Step 1
            Me.Controls("pplTop" & i).Visible = Segs(1, (5 - i), 1)
            Me.Controls("pplTopL" & i).Visible = Segs(1, (5 - i), 2)
            Me.Controls("pplTopR" & i).Visible = Segs(1, (5 - i), 3)
            Me.Controls("pplMid" & i).Visible = Segs(1, (5 - i), 4)
            Me.Controls("pplBotL" & i).Visible = Segs(1, (5 - i), 5)
            Me.Controls("pplBotR" & i).Visible = Segs(1, (5 - i), 6)
            Me.Controls("pplBot" & i).Visible = Segs(1, (5 - i), 7)
        Next i

The error can be seen here: http://www.jamesbuckland.com/garage/error.jpg

The controls im changing are image boxes is this why it will not work? Sorry for all the questions and thanks for all the help.

Thanks, James

[kadghar]

Thanks, I have it set up like this but im still getting an error:
...
The error can be seen here: https://<br /> http://www.jamesbuck...rage/error.jpg

Thanks, James

when this error occurs, pass the mouse over i3 (anyone) to see its current value at that moment.

its because saltop1 or saltop 2 or... does not exist, or because segs(3,5,1) or segs(3,4,1) or segs(3,3,1).... is not defined, or has not been set to a value or is not a boolean.

But that code you wrote, seems all right to me.

[JBuckland]

Only the first loop gets a value and the i3 is 1, ive looked over all the naming and it all looks fine. How can I give a value to every space in my array? Will this help?

Thanks, James

[kadghar]

Only the first loop gets a value and the i3 is 1, ive looked over all the naming and it all looks fine. How can I give a value to every space in my array? Will this help?

Thanks, James

They already have one, it's 'False' by default.

the only thing that comes to my mind is:

what kind of control is salTop1?? i mean, is it a command button, or a combo box, or what is it?.

Or pass the mouse over Segs (any of them) when the error occurs, and check its values. Check if Segs(3, 5, 1) has a boolean's value (true or false)

[JBuckland]

salTop1 etc. are Pictures Box's with an image of a segment in them. I can change them to something else if it will help.

Thanks, James

[kadghar]

salTop1 etc. are image box's with an image of a segment in them. I can change them to something else if it will help.

Thanks, James

No no, image boxes does have the visible property, ... and what about the boolean's value? is it set to True or False?

[kadghar]

other thing that comes to my mind is that maybe the image boxes have another parent, like a frame.

so you might need to put the complete 'path':
[CODE=vb]me.frame1.contr ols("something" & i).visible = true.[/CODE]

[JBuckland]

They all seem to have values:


Thanks, James

[JBuckland]

Thank you so much. My stupid mistake i had them in a group box for visual effect and once i added the name for the groups it worked perfectly. Thanks for all the help I really appreciate it and im sure I can only learn from my mistakes.

Thanks, James

[kadghar]

Thank you so much. My stupid mistake i had them in a group box for visual effect and once i added the name for the groups it worked perfectly. Thanks for all the help I really appreciate it and im sure I can only learn from my mistakes.

Thanks, James

L O L, dont be so rude with that poor mistake.

im glad it helped you.