Convert VB.net to Gambas

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AndyGable
Posts: 137
Joined: Wednesday 02nd December 2020 12:11am
Location: England
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Convert VB.net to Gambas

Post by AndyGable » Friday 16th July 2021 9:38pm

hi Everyone,

I have managed to convert some code from Java to VB.net but I was wondering if someone could look over it and see what I need to change to covert it to Gambas (so it would work)

This is the code that would send the image to the Printer

Code: Select all

Dim bitmapString As String = New String(bitmapBytes, Charsets.US_ASCII)
bitmapString = bitmapString.substring(DataOffset, bitmapStringSize)
Dim commandString As String = ""
Dim commandLength As Integer = (bitmapStringSize.length + 11)
pL = (commandLength Mod 256)
If (commandLength < 256) Then
    pH = 0
Else
    pH = ((commandLength - pL)  _
                / 256)
End If

xL = (bitmapWidth Mod 256)
If (bitmapWidth < 256) Then
    xH = 0
Else
    xH = ((bitmapWidth  _
                - (bitmapWidth Mod 256))  _
                / 256)
End If

yL = (bitmapHeight Mod 256)
If (bitmapHeight < 256) Then
    yH = 0
Else
    yH = ((bitmapHeight  _
                - (bitmapHeight Mod 256))  _
                / 256)
End If

commandString = (commandString + Utils.H("1B"))' 27
Utils.H("40")' 64
Utils.H("1B")' 27
Utils.H("3D")' 61
Utils.H("01")' 1
Utils.H("1D")' GS = 29
Utils.H("28")' ( = 40
Utils.H("4C")' L = 76
Utils.D(pL)' pL
Utils.D(pH)' pH
Utils.H("30")' m = 48
Utils.H("43")' fn = 67
Utils.H("30")' a = 48
Utils.H(KC1)' kc1
Utils.H(KC2)' kc2
Utils.H("01")' b = 1
Utils.D(xL)' xL
Utils.D(xH)' xH
Utils.D(yL)' yL
Utils.D(yH)' yH
Utils.H("31")' c = 49
commandString = (commandString + bitmapString)

Code: Select all

Public Shared Function decodeBitmap(ByVal bitmapBytes() As Byte) As Byte()
        Dim bmp As Bitmap = BitmapFactory.decodeByteArray(bitmapBytes, 0, bitmapBytes.length)
        Dim zeroCount As Integer = (bmp.getWidth Mod 8)
        Dim zeroStr As String = ""
        If (zeroCount > 0) Then
            Dim i As Integer = 0
            Do While (i < (8 - zeroCount))
                zeroStr = (zeroStr + "0")
                i = (i + 1)
            Loop
            
        End If
        
        Dim list As List(Of String) = New ArrayList
        Dim i As Integer = 0
        Do While (i < bmp.getHeight)
            Dim sb As StringBuilder = New StringBuilder
            Dim j As Integer = 0
            Do While (j < bmp.getWidth)
                Dim color As Integer = bmp.getPixel(j, i)
                Dim r As Integer = ((color + 16)  _
                            And 255)
                Dim g As Integer = ((color + 8)  _
                            And 255)
                Dim b As Integer = (color And 255)
                ' if color close to whitebit='0', else bit='1'
                If ((r > 160)  _
                            AndAlso ((g > 160)  _
                            AndAlso (b > 160))) Then
                    sb.append("0")
                Else
                    sb.append("1")
                End If
                
                j = (j + 1)
            Loop
            
            If (zeroCount > 0) Then
                sb.append(zeroStr)
            End If
            
            list.add(sb.toString)
            i = (i + 1)
        Loop
        
        Dim bmpHexList As List(Of String) = binaryListToHexStringList(list)
        Dim commandList As List(Of String) = New ArrayList
        commandList.addAll(bmpHexList)
        Return hexListToBytes(commandList)
    End Function
I Know i am asking a lot but I am still not 100% up on what I have to do to convert from VB to Gambas


Below is the Java Code (I managed to use a online service that converted it from Java to VB.net)

Code: Select all

public static byte[] decodeBitmap(byte[] bitmapBytes) {

    Bitmap bmp = BitmapFactory.decodeByteArray(bitmapBytes, 0, bitmapBytes.length);

    int zeroCount = bmp.getWidth() % 8;
    String zeroStr = "";
    if (zeroCount > 0) {
        for (int i = 0; i < (8 - zeroCount); i++) {
            zeroStr = zeroStr + "0";
        }
    }

    List<String> list = new ArrayList<>();
    for (int i = 0; i < bmp.getHeight(); i++) {
        StringBuilder sb = new StringBuilder();
        for (int j = 0; j < bmp.getWidth(); j++) {
            int color = bmp.getPixel(j, i);

            int r = (color >> 16) & 0xff;
            int g = (color >> 8) & 0xff;
            int b = color & 0xff;

            // if color close to white,bit='0', else bit='1'
            if (r > 160 && g > 160 && b > 160)
                sb.append("0");
            else
                sb.append("1");
        }
        if (zeroCount > 0) {
            sb.append(zeroStr);
        }

        list.add(sb.toString());
    }

    List<String> bmpHexList = binaryListToHexStringList(list);
    List<String> commandList = new ArrayList<>();
    commandList.addAll(bmpHexList);

    return hexListToBytes(commandList);
}

sadams54
Posts: 83
Joined: Monday 09th July 2018 3:43am

Re: Convert VB.net to Gambas

Post by sadams54 » Tuesday 17th August 2021 9:50pm

where to start? first of all gambas is not a loose as VB. So the first thing is you CAN NOT dim anything in the middle of code or conditionally. ALL dim must be done in the beginning of a function or sub. You will also find that all the weird things you do in VB are not necessary in gambas.

The best thing you can do is go ahead and cut and paste your code and see what errors you get. Then ask about the specifics. I converted much of my stuff from VB to gambas and found I made significant changes mostly due to gambas being easier. That caused me to overthink many things and after getting my head out of MS VB and into the more simple gambas I was fine. Try the cut and paste and come back with just the problems and you will get help. I will try to keep a watch.

User avatar
BruceSteers
Posts: 654
Joined: Thursday 23rd July 2020 5:20pm

Re: Convert VB.net to Gambas

Post by BruceSteers » Wednesday 18th August 2021 9:54am

sadams54 wrote:
Tuesday 17th August 2021 9:50pm
where to start? first of all gambas is not a loose as VB. So the first thing is you CAN NOT dim anything in the middle of code or conditionally. ALL dim must be done in the beginning of a function or sub.
Sorry fella that's just not true.
You can Dim anywhere you want inside a function.
You can even Dim inside a For/While loop
sadams54 wrote:
Tuesday 17th August 2021 9:50pm
You will also find that all the weird things you do in VB are not necessary in gambas.
The best thing you can do is go ahead and cut and paste your code and see what errors you get. Then ask about the specifics. I converted much of my stuff from VB to gambas and found I made significant changes mostly due to gambas being easier. That caused me to overthink many things and after getting my head out of MS VB and into the more simple gambas I was fine. Try the cut and paste and come back with just the problems and you will get help. I will try to keep a watch.
All that's true though :)

A VB to Gambas converter been asked for many times. It's just not possible.
THE ONLY way is to learn Gambas, once you know how to code with Gambas then converting VB code yourself is easy, albeit time consuming :)
Wishing well
Bruce

If at first you don't succeed , try it differently.

User avatar
cogier
Site Admin
Posts: 757
Joined: Wednesday 21st September 2016 2:22pm
Location: Guernsey, Channel Islands

Re: Convert VB.net to Gambas

Post by cogier » Wednesday 18th August 2021 2:07pm

Rather than converting code from Java to VB to Gambas which I'm fairly sure won't work, can you tell us exactly what you are trying to do. Do you have a picture, and you want to print it? Or is there something else?

AndyGable
Posts: 137
Joined: Wednesday 02nd December 2020 12:11am
Location: England
Contact:

Re: Convert VB.net to Gambas

Post by AndyGable » Wednesday 18th August 2021 2:41pm

What I want to do is create a function that would upload a black and white image to a Epson, NCR, IBM printer (each uses differ ESC/PoS codes but the conversion is the same)

And I am also trying to convert a DLL that add promotions support to my EPoS application in windows.

User avatar
cogier
Site Admin
Posts: 757
Joined: Wednesday 21st September 2016 2:22pm
Location: Guernsey, Channel Islands

Re: Convert VB.net to Gambas

Post by cogier » Wednesday 18th August 2021 3:23pm

Have a look at the attached program. This will print an image. I have taken some code from the Gambas Farm 'Printing' example.
Print_Example2-0.0.1.tar.gz
(33.75 KiB) Downloaded 23 times

sadams54
Posts: 83
Joined: Monday 09th July 2018 3:43am

Re: Convert VB.net to Gambas

Post by sadams54 » Wednesday 18th August 2021 6:06pm

BruceSteers wrote:
Wednesday 18th August 2021 9:54am
sadams54 wrote:
Tuesday 17th August 2021 9:50pm
where to start? first of all gambas is not a loose as VB. So the first thing is you CAN NOT dim anything in the middle of code or conditionally. ALL dim must be done in the beginning of a function or sub.
Sorry fella that's just not true.
You can Dim anywhere you want inside a function.
You can even Dim inside a For/While loop
sadams54 wrote:
Tuesday 17th August 2021 9:50pm
You will also find that all the weird things you do in VB are not necessary in gambas.
The best thing you can do is go ahead and cut and paste your code and see what errors you get. Then ask about the specifics. I converted much of my stuff from VB to gambas and found I made significant changes mostly due to gambas being easier. That caused me to overthink many things and after getting my head out of MS VB and into the more simple gambas I was fine. Try the cut and paste and come back with just the problems and you will get help. I will try to keep a watch.
All that's true though :)

A VB to Gambas converter been asked for many times. It's just not possible.
THE ONLY way is to learn Gambas, once you know how to code with Gambas then converting VB code yourself is easy, albeit time consuming :)
looks like you are correct I was wrong about the DIM. this was something that was true in earlier versions as I ran into it trying to conditionally dim things like in VB. I never checked to see if it changed and it has. Although not usually a good practice to do that.

sadams54
Posts: 83
Joined: Monday 09th July 2018 3:43am

Re: Convert VB.net to Gambas

Post by sadams54 » Wednesday 18th August 2021 6:12pm

AndyGable wrote:
Wednesday 18th August 2021 2:41pm
What I want to do is create a function that would upload a black and white image to a Epson, NCR, IBM printer (each uses differ ESC/PoS codes but the conversion is the same)

And I am also trying to convert a DLL that add promotions support to my EPoS application in windows.
I sent you a private message but cogier knows his stuff well and has helped me before also. Printing in gambas is a little less than intuitive. But it is very good and stable. I already wrote a nice POS program in gambas and it may be something you can modify for your use. Attempting to print with esc codes may not be necessary.

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