What is the equivalent of __FILE__ and __LINE__ in C#?

Where is __LINE__ and __FILE__ in C#?

In C++ and in PHP and other languages, a great logging feature is the ability to log the file and line number where the log occurs.

These unfortunately do not exist.  I have been searching even in the latest .NET 4.0 and haven’t found them.  If they are there, they are hidden. Having these two variables is an extremely useful feature in other languages and it appears to be a feature very overlooked by the C# developers. However, maybe they didn’t overlook it.  Maybe there is a good reason that it is not there.

Getting __LINE__ and __FILE__ in C# when in debugging mode

There were a couple of solutions floating around online but many of them only worked with debugging enabled (or in release if the pdb file is in the same directory).

Here is one example that only works in debugging (or in release if the pdb file is in the same directory).

StackHelper.cs

using System;
using System.Diagnostics;

namespace FileAndLineNumberInCSharpLog
{
    public static class StackHelper
    {

        public static String ReportError(string Message)
        {
            // Get the frame one step up the call tree
            StackFrame CallStack = new StackFrame(1, true);

            // These will now show the file and line number of the ReportError
            string SourceFile = CallStack.GetFileName();
            int SourceLine = CallStack.GetFileLineNumber();

            return "Error: " + Message + "\nFile: " + SourceFile + "\nLine: " + SourceLine.ToString();
        }

        public static int __LINE__
        {
            get
            {
                StackFrame CallStack = new StackFrame(1, true);
                int line = new int();
                line += CallStack.GetFileLineNumber();
                return line;
            }
        }

        public static string __FILE__
        {
            get
            {
                StackFrame CallStack = new StackFrame(1, true);
                string temp = CallStack.GetFileName();
                String file = String.Copy(String.IsNullOrEmpty(temp)?"":temp);
                return String.IsNullOrEmpty(file) ? "": file;
            }
        }
    }
}

Here is a little Program.cs that shows how to use it.

using System;

namespace FileAndLineNumberInCSharpLog
{
    class Program
    {
        static void Main(string[] args)
        {
            int x = 100;
            int y = 200;
            int z = x * y;
            Console.WriteLine(StackHelper.ReportError("New Error"));
        }
    }
}

Unfortunately if the above does only work in release if the pdb file is available.

Getting __LINE__ and __FILE__ in C# when in debugging mode

Well, according to this MSDN forum post, it simply cannot be done.
http://social.msdn.microsoft.com/Forums/en-US/csharpgeneral/thread/6a7b021c-ec81-47c5-8f6a-2e280d548f3f

If I ever find a way to do it, I will post it.

So for troubleshooting a production file at a customer’s site, you pretty much have to send out your pdb file to them when they need it.  There are a lot of benefits to C# and this lacking feature is one of the eye sores.

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