How to convert this code from vb6 to c#

Thach Le

Dear All,
I'm new in C#, It's difiifcult for me to change this code in vb6 to c#
Could anybody help me to convert this code to c#
Private Static Sub ShowData(Data As String)
Dim stx, ret, ret1 As Integer
Dim valcom As Variant
Dim strg As String
strg = strg & Data
stx = InStr(strg, Chr$(2))

If stx Then
ret = InStr(stx + 1, strg, Chr$(13))
Else
ret = 0
End If
If ret Then
If ret - stx <> 16 Then
strg = vbNullString
Exit Sub
End If
If Len(strg) < 17 Then Exit Sub
valcom = Val(Mid(strg, stx + 4, 6))
If Not IsNumeric(valcom) Then
strg = vbNullString
Exit Sub
End If
ret = Asc(Mid(strg, stx + 2, 1)) And 2
ret1 = Asc(Mid(strg, stx + 1, 1)) And 7
strg = vbNullString
If ret1 = 2 Then
lbldaucan = Format(IIf(ret - 2, valcom, valcom * (-1)), "#,#")
ElseIf ret1 = 3 Then
lbldaucan = Format(IIf(ret - 2, valcom / 10, (valcom / 10) * (-1)), "0.0")
ElseIf ret1 = 4 Then
lbldaucan = Format(IIf(ret - 2, valcom / 100, (valcom / 100) * (-1)), "0.00")
ElseIf ret1 = 5 Then
lbldaucan = Format(IIf(ret - 2, valcom / 1000, (valcom / 1000) * (-1)), "0.000")
End If
'lblcom1.Caption = valcom
If lbldaucan = "" Then
lbldaucan = 0
End If
End If
End Sub

7 Replies

Know the answer? Post it — somebody with the same question will find it here.

Vulpes15y ago
Accepted answer
There's considerable scope for both manual translators and programmatic translators (particularly the free ones) to run aground when converting this piece of code to C#.

I'd therefore suggest that you add a reference to Microsoft.VisualBasic.dll to your C# project so that you can use replicas of the original VB6 functions in your code, rather than trying to convert them to the closest .NET equivalents. Even then there are some problems to overcome.

Anyway here's my attempt (I assume lbldaucan is a label):

using VB = Microsoft.VisualBasic;

// ....

private static void ShowData(string Data)
{
int ret, ret1;
object varValcom;
double valcom;
string strg = Data;
int stx = VB.Strings.InStr(strg, "\x02", VB.Constants.vbBinaryCompare);

if (stx != 0)
{
ret = VB.Strings.InStr(stx + 1, strg, "\r", VB.Constants.vbBinaryCompare);
}
else
{
ret = 0;
}

if (ret != 0)
{
if ((ret - stx) != 16)
{
strg = null;
return;
}

if (strg.Length < 17) return;
varValcom = VB.Conversion.Val(VB.Strings.Mid(strg, stx + 4, 6));

if (!VB.Information.IsNumeric(varValcom))
{
strg = null;
return;
}
else
{
valcom = VB.Conversion.Val(varValcom); // safe to use double value now
}

ret = VB.Strings.Asc(VB.Strings.Mid(strg, stx + 2, 1)) & 2;
ret1 = VB.Strings.Asc(VB.Strings.Mid(strg, stx + 1, 1)) & 7;
strg = null;

if (ret1 == 2)
{
lbldaucan.Text = VB.Strings.Format(VB.Interaction.IIf((ret - 2) != 0, valcom, valcom * (-1)), "#,#");
}
else if (ret1 == 3)
{
lbldaucan.Text = VB.Strings.Format(VB.Interaction.IIf((ret - 2) != 0, valcom / 10, (valcom / 10) * (-1)), "0.0");
}
else if (ret1 == 4)
{
lbldaucan.Text = VB.Strings.Format(VB.Interaction.IIf((ret - 2) != 0, valcom / 100, (valcom / 100) * (-1)), "0.00");
}
else if(ret1 == 5)
{
lbldaucan.Text = VB.Strings.Format(VB.Interaction.IIf((ret - 2) != 0, valcom / 1000, (valcom / 1000) * (-1)), "0.000");
}
if (lbldaucan.Text == "") lbldaucan.Text = "0";
}
}
Thach Le15y ago
Hi,
Thanks for your all reply,
i sorted out my problem, i don't use ComEvent as last code,
i use Thread.Sleep;
Private void Com_OnCom(object sender, EventArgs e)
{
Thread.Sleep(200);
if(Com.InBufferCount>0)
        {
          try
          {
                  string Buffer=(string)Com.Input;
                  //Call function ShowData
                  ShowData(Buffer);
          }
          catch(Exception ex)
          {

          }
        }

}
This project to get weigh from Digital scale (Mettler Toledo)
Vulpes15y ago
Regarding the first error, it sounds like Com.CommEvent is a short but MSCommLib.OnCommConstants.comEvReceive is a different integral type, perhaps an int.

To fix it I'd try:

switch ((int)Com.CommEvent)

Regarding the second error, if buffer is really a string (it's difficult to see how the VB6 code could work if it were a byte array) then you shouldn't need to convert it to unicode - because all .NET strings are unicode in any case.

So, I'd try:

ShowData((string)buffer);
Mittal Sejpal15y ago
http://converter.telerik.com/

this link gives convertor which will convert vb6 code csharp

hope it helps you
Mayur Gujrathi15y ago
http://www.developerfusion.com/tools/convert/csharp-to-vb/

try this
Thach Le15y ago
Hi Vulpes,
Thanks for your reply,
i sorted out the problem with your suggest but when i call this void and have a little problem
this code i used in VB6

Private Sub Comm_OnComm()
Select Case Comm.CommEvent
Case comEvReceive
Dim Buffer As Variant
Buffer = Comm.Input
ShowData (StrConv(Buffer, vbUnicode))
End Select
End Sub

And i tried to migrate to C Sharp
private void Com_OnComm(object sender, EventArgs e)
{
         object Buffer;
         switch (Com.CommEvent)
         {
                 case MSCommLib.OnCommConstants.comEvReceive:
                  //"Cannot implicitly convert type 'MSCommLib.OnCommConstants' to 'short'. An explicit conversion exists (are you missing a cast?)"
                 Buffer = Com.Input;
                 //string convstr=System.Text.Encoding.GetEncoding(1252).GetString(Buffer);
                 ShowData(VB.Strings.StrConv(Buffer,Encoding.UTF8.GetBytes(Buffer));
           //The best overloaded method match for 'Microsoft.VisualBasic.Strings.StrConv(string, Microsoft.VisualBasic.VbStrConv, int)' has some invalid arguments

                 break;
         }
}

Could you check and fix for me?
Thanks in advance!
Satyapriya Nayak15y ago
Hi thach,

There are many converter available in internet use those

One is below

http://www.developerfusion.com/tools/convert/vb-to-csharp/

Thanks