octal numbers - how to use

Question

I searched huge part of documentations and forums but something is wrong with Visual Studio C# 2010. Maybe I'm wrong but see my code below:

I try to use octal number constants and assign them to "int" variable.

// variable definition
byte L;

// first octal number 021 (17-decimal)
L = 021;
// After that line I see (on debug) L=21
// 021 was treated as decimal not octal !!!

// next test, octal number 056 (46-decimal)
L = 056;
// and I see (on debug) L=56, again wrong !!!

Why????

Vulpes · Answer

One further thought. Unlike C/C++ string literals can be used as cases in the switch statement in C#. So as long as you make the conversion to an octal string before entering the switch you could use octal string literals for your cases.

Vulpes · Answer

I agree that it is very disappointing that C# doesn't support octal literals particularly as all the other leading .NET languages (VB.NET C++/CLI and F#) do support them. I suppose you could 'farm out' your octal work to a dll written in one of these languages and then add a reference to that dll to your C# project but it's a tedious workaround. Instead of the switch statement you could use an if/else if/else ladder.

belamy · Answer

ok but in switch/case I can not use Convert only constant values. Unfortunately I've to check my variable at a lot of cases. I use this variable to check a type of packet that is sending after my variable. All documentation uses octal values to describe type of packet. Poor Ms Visual C# very poor. PS. I used a lot of compilers C/C++ and even C compilers for old 8-bit uP can use octal constant.

Vulpes · Answer

Unfortunately C# doesn't support octal literals only decimal and hexadecimal. So 021 and 056 are interpreted as decimal 21 and 56 respectively. FWIW you can convert from and to octal strings with: byte L = Convert.ToByte(021 8); // and string oct = Convert.ToString(L 8); but of course that's not much use for arithmetic purposes.