Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger doesn't handle hex strings

[rolfbjarne]

Submitted by a community member on 2014-08-14 16:38 UTC

In Microsoft Visual basic you can convert a hex string starting with &H to an integer e.g. with the following code:

Module Module1
    Sub Main()
        System.Console.WriteLine(Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger("&H02B7"))
        Console.ReadLine()
    End Sub
End Module

The following Adrift bug suggests this isn't working in mono-basic 2.10: http://www.adrift.co/bug/18434

Conversion from string "&H02B7" to type 'Integer' is not valid.
at Microsoft.VisualBasic.CompilerServices.IntegerType.FromString (System.String.Value) [0x00000] in <filename unknown: 0
at Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger (System.String.Value) [0x00000] in <filename unknown: 0

(I'm on Windows here where mono-basic doesn't seem to be available so I haven't run my test module in mono)

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Xamarin Bugzilla comment 1 by a community member on 2014-08-14 19:51 UTC

I've compiled the above module in ArchLinux with vbnc2 and confirmed the issue:

Unhandled Exception:
System.InvalidCastException: Conversion from string "&H02B7" to type 'Integer' is not valid. ---> System.FormatException: Input string was not in the correct format
  at System.Int32.Parse (System.String s) [0x00000] in <filename unknown>:0 
  at Microsoft.VisualBasic.CompilerServices.IntegerType.FromString (System.String Value) [0x00000] in <filename unknown>:0 
  --- End of inner exception stack trace ---
  at Microsoft.VisualBasic.CompilerServices.IntegerType.FromString (System.String Value) [0x00000] in <filename unknown>:0 
  at Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger (System.String Value) [0x00000] in <filename unknown>:0 
  at Module1.Main () [0x00000] in <filename unknown>:0 

[ERROR] FATAL UNHANDLED EXCEPTION: System.InvalidCastException: Conversion from string "&amp;H02B7" to type 'Integer' is not valid. ---\> System.FormatException: Input string was not in the correct format
  at System.Int32.Parse (System.String s) [0x00000] in <filename unknown>:0 
  at Microsoft.VisualBasic.CompilerServices.IntegerType.FromString (System.String Value) [0x00000] in <filename unknown>:0 
  --- End of inner exception stack trace ---
  at Microsoft.VisualBasic.CompilerServices.IntegerType.FromString (System.String Value) [0x00000] in <filename unknown>:0 
  at Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger (System.String Value) [0x00000] in <filename unknown>:0 
  at Module1.Main () [0x00000] in <filename unknown>:0

Xamarin Bugzilla comment 2 by a community member on 2014-08-15 09:09 UTC

Additionally I noticed that the mono code is passing the string directly to System.Int32.Parse.

I tested System.Int32.Parse in Microsoft Visual Basic and it throws a FormatException on this string, so there has to be some parsing in between.

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Reference: https://bugzilla.xamarin.com/show_bug.cgi?id=22124

[TheCycoONE]

I created this ticket on Bugzilla.