How can I obtain the named arguments from a console application in the form of a Dictionary?

Question

I have a console application called MyTool.exe

What is the simplest way to collect the named arguments passed to this console applicaiton and then to put them in a Dictionarty<string, string>() which will have the argument name as the key and the value as the argument?

for example:

MyTool foo=123432 bar=Alora barFoo=45.9

I should be able to obtain a dictionary which will be:

MyArguments["foo"]=123432 
MyArguments["bar"]="Alora"
MyArguments["barFoo"]="45.9"

Couldn't you use a more standard format thus allowying your appliction to interop with others better? Have a peek at http://stackoverflow.com/questions/491595/best-way-to-parse-command-line-arguments-in-c — John Mitchell, Jul 11 '12 at 09:53

score 33 · Answer 1 · edited Nov 06 '17 at 14:41

Use this Nuget package

V1.9.x - Command Line Parser Library ^{(CodePlex - Going away soon and out of date)}
V2+ - Command Line Parser ^{(Ongoing support)}

Takes seconds to configure and adds instant professional touch to your application.

// Define a class to receive parsed values
class Options {
  [Option('r', "read", Required = true,
    HelpText = "Input file to be processed.")]
  public string InputFile { get; set; }

  [Option('v', "verbose", DefaultValue = true,
    HelpText = "Prints all messages to standard output.")]
  public bool Verbose { get; set; }

  [ParserState]
  public IParserState LastParserState { get; set; }

  [HelpOption]
  public string GetUsage() {
    return HelpText.AutoBuild(this,
      (HelpText current) => HelpText.DefaultParsingErrorsHandler(this, current));
  }
}

// Consume them
static void Main(string[] args) {
  var options = new Options();
  if (CommandLine.Parser.Default.ParseArguments(args, options)) {
    // Values are available here
    if (options.Verbose) Console.WriteLine("Filename: {0}", options.InputFile);
  }
}

2.0.*-beta seems to change things a little: https://github.com/gsscoder/commandline - including a different options layout. — WernerCD, Jun 15 '16 at 15:14
@WernerCD Guess we need to update this answer once it gets released. Thanks for pointing it out. — Mrchief, Jun 15 '16 at 15:46

score 15 · Answer 2 · answered Jul 13 '12 at 16:59

15

Here's how this can be done in the most simple way:

    static void Main(string[] args)
    {
        var arguments = new Dictionary<string, string>();

        foreach (string argument in args)
        {
            string[] splitted = argument.Split('=');

            if (splitted.Length == 2)
            {
                arguments[splitted[0]] = splitted[1];
            }
        }
    }

Note that:

Argument names are case sensitive
Providing the same argument name more than once does not produce an error
No spaces are allowed
One = sign must be used

answered Jul 13 '12 at 16:59

Kay Zed

1,304
2
21
31

Overwriting a key is a deadly type of "silent error". The program does not complain, and misinterprets what the user specifies. Granted for the majority of cases it won't matter. – hova Jul 13 '12 at 18:31
hova: this serves as an example. – Kay Zed Jul 13 '12 at 19:10
This is my approach, as well. I like the concept of using "pure" C# and .NET as opposed to third-party libs, when viable. – Christiano Kiss Jan 08 '21 at 13:14

score 4 · Answer 3 · edited Jun 09 '21 at 09:29

4

if you have a "=" in your parameter values, a safer option would be:

private static Dictionary<string, string> ResolveArguments(string[] args)
{
    if (args == null)
        return null;

    if (args.Length > 0)
    {
        var arguments = new Dictionary<string, string>();
        foreach (string argument in args)
        {
            int idx = argument.IndexOf('=');
            if (idx > 0)
                arguments[argument.Substring(0, idx)] = argument.Substring(idx+1);
        }
        return arguments;
    }

    return null;
}

edited Jun 09 '21 at 09:29

Matas Vaitkevicius

58,075
31
238
265

answered Jan 25 '17 at 06:42

Robert Mc Menamin

41
1

2

It seems to me that instead of "if (args.Length > 1)", you should have "if (args.Length >= 1)" or "if (args.Length > 0)". In the case of exactly 1 argument, your code returns null. – Cityonhill93 Oct 09 '17 at 16:34

score 2 · Answer 4 · answered Aug 02 '12 at 07:28

2

I don't see why this code is bad? hova?

        var arguments = new Dictionary<string, string>();
        foreach (var item in Environment.GetCommandLineArgs())
        {
            try
            {
                var parts = item.Split('=');
                arguments.Add(parts[0], parts[1]);
            }
            catch (Exception ex)
            {
                // your error handling here....
            }

answered Aug 02 '12 at 07:28

Stig

1,323
16
22

why have you put Environment.GetCommandLineArgs instead of just args? – essential Sep 03 '19 at 12:39
4

Then, the code example is independent of where you run it, just paste it in somewhere, and it will run. – Stig Sep 06 '19 at 07:42

score 0 · Answer 5 · answered Apr 27 '23 at 10:39

You can use Microsoft.Extensions.Configuration.CommandLine.

IConfiguration configuration = new ConfigurationBuilder()
    .AddJsonFile("appsettings.json", optional: true)
    .AddEnvironmentVariables()
    .AddCommandLine(args) // here
    .Build();

Than you can execute your app like this:

MyConsoleApplication.exe --myParameterName myvalue

Check this blog post and docs for details.

How can I obtain the named arguments from a console application in the form of a Dictionary?

5 Answers5

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