Escaping command line arguments in C# for Urls and Local and Network Paths

Question

How do I provide an input string with automatic escaping to a console application?

I mean inside my code, I can do

public static void main(string[] args)
{
     string myURL; 
     myFolder = @"C:\temp\january\";  //just for testing
     myFolder = args[0]; // I want to do this eventually
}

How can I provide values to myFolder without me having to escape it manually via command line?

If possible, I want to avoid calling this app like this:

C:\test> myapplication.exe "C:\\temp\\january\\"

EDIT: instead I'd prefer calling the app like this if possible

    C:\test> myapplication.exe @"C:\temp\january\"

Thank you.

EDIT:

This is actually for a console application that calls Sharepoint Web services. I tried

  string SourceFileFullPath, SourceFileName, DestinationFolder, DestinationFullPath;

            //This part didn't work. Got Microsoft.SharePoint.SoapServer.SoapServerException
            //SourceFileFullPath = args[0]; // C:\temp\xyz.pdf
            //SourceFileName = args[1];     // xyz.pdf
            //DestinationFolder = args[2]; // "http://myserver/ClientX/Performance" Reports


            //This worked.   
            SourceFileFullPath = @"C:\temp\TestDoc2.txt";
            SourceFileName = @"TestDoc2.txt";
            DestinationFolder = @"http://myserver/ClientX/Performance Reports";
            DestinationFullPath = string.Format("{0}/{1}", DestinationFolder, SourceFileName);

Please check this http://stackoverflow.com/questions/5179389/at-sign-in-file-path-string — Akshay Joy, Apr 10 '13 at 17:15
You stated how you **don't want to call the application.** How exactly **do you want to call the application?** — Mike Perrenoud, Apr 10 '13 at 17:16
why would you c#-escape the input at the command line? that makes no sense - the command-line is not c# — Marc Gravell, Apr 10 '13 at 17:17
Perhaps if you try to pass your argument you will discover that there is no need to escape anything — Steve, Apr 10 '13 at 17:19

Aasmund Eldhuset · Accepted Answer · 2013-06-19T13:26:52.140

3

The requirement to escape \ inside a string if it is not a verbatim string (one that starts with @) is a C# feature. When you start your application from a console, you are outside of C#, and the console does not consider \ to be a special character, so C:\test> myapplication.exe "C:\temp\january" will work.

Edit: My original post had "C:\temp\january\" above; however, the Windows command line seems to also handle \ as an escape character - but only when in front of a ", so that command would pass C:\temp\january" to the application. Thanks to @zimdanen for pointing this out.

Please note that whatever you put between quotes in C# is a representation of a string; the actual string may be different - for instance, \\ represents a single \. If you use other means to get strings into the program, such as the command line arguments or by reading from a file, the strings do not need to follow C#'s rules for string literals. The command line has different rules for representation, in which a \ represents itself.

edited Jun 19 '13 at 13:26

answered Apr 10 '13 at 17:19

Aasmund Eldhuset

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This isn't quite true, because putting `"C:\temp\january\"` as the arg will come in as `C:\temp\january"` to the app - `\"` is treated as an escaped quote. – zimdanen Jun 19 '13 at 13:07
@zimdanen: Not in the standard Windows shell, to my knowledge - since `\\` is the path separator on Windows, it would be cumbersome to have it act as an escape character. – Aasmund Eldhuset Jun 19 '13 at 13:13
I'm working on one now - my code prints out the args right away (`Console.WriteLine(string.Join(Environment.NewLine, args));`), and, using the input `...\Log\Log\bin\Debug>Log.exe "c:\test\"`, I get the output `c:\test"`. – zimdanen Jun 19 '13 at 13:18
1

@zimdanen: I stand corrected; it looks like \ acts as an escape character only when in front of a " ... :S I've updated the post (and my dislike for cmd.) – Aasmund Eldhuset Jun 19 '13 at 13:23

score 0 · Answer 2 · answered Apr 10 '13 at 17:19

“The prefix “@” enables the use of keywords as identifiers, which is useful when interfacing with other programming languages. The character @ is not actually part of the identifier, so the identifier might be seen in other languages as a normal identifier, without the prefix. An identifier with an @ prefix is called a verbatim identifier. Use of the @ prefix for identifiers that are not keywords is permitted, but strongly discouraged as a matter of style.”

You can use one of the reserved words of c# with the @ symbol

ex:-

  string @int = "senthil kumar";
    string @class ="MCA";

2.Before a string specially when using the file paths

string filepath = @"D:\SENTHIL-DATA\myprofile.txt";

instead of

string filepath = "D:\\SENTHIL-DATA\\myprofile.txt";

For a Multi lined text

string ThreeIdiots = @"Senthil Kumar, Norton Stanley, and Pavan Rao!";
```
MessageBox.Show(ThreeIdiots);
```

instead of

string ThreeIdiots = @"Senthil Kumar,\n   Norton Stanley,and Pavan Rao!";

Escaping command line arguments in C# for Urls and Local and Network Paths

2 Answers2

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