CommandLineArgsHelper

A parsing class to dramatically simplify working with command line arguments in a .Net application (e.g. console, client, or even web application).

It supports a variety of parameter syntaxes, and seamlessly parses all of them into a simplified Dictionary interface of key value string pairs. This library remains loosly coupled, and therefore can be used for both dyanmic arguments (that are not pre-defined) and static arguments pre-defined and/or used via Strongly Typed class.

Nuget Package:

To use this in your project, add the CommandLineArgsHelper NuGet package to your project.

Why another Library?

Many of the existing libraries are based on the constrained paradigm that arguments should be bound to strongly typed objects. However, for many implementations, this is a limiting approach that means you have to re-compile the app to support new parameters; not supporting dynamic behavior and possibly making the model, that params bind to, force you to have strange naming conventions in your code.

Instead, this provides a loosely coupled approach that is more generic and allows you to support dynamic behavior as well as strongly typed behavior by simply putting keys into property getter's (if you like).

Original Code forked from:

The Code has been adapted from the original source located at: https://www.codeproject.com/Articles/3111/C-NET-Command-Line-Arguments-Parser

But it has been updated and simplified as follows:

• Updated with new C# syntax
• More robust parsing for wider array of parameter syntaxes, keys/values with spaces, etc.
• Enhanced class wrapper (e.g. exposed read only dictionary for enumeration)
• Support for both key/value parameter pairs, as well as simple boolean flags (param is defined/exists or not)
• Improved thread safety
• Eliminated code duplication

Usage:

Usage is extremely simple:

//Intialize given a string array of arguments (string[])...
//  1) injected into console app main routine
//  2) accessed via Environment.GetCommandLineArgs()
var commandLineArgHelper = new CommandLineArgsHelper(args);

var value = commandLineArgsHelper["paramKeyName"];

Console.WriteLine($"paramKeyName == {value]")

Dynamic Argument Example:

Command line with all of the following (mixed syntaxes fully supported):

-size=100 /height:'400' /day:"happy birthday" -tgif="Thank God It's Friday" -AmINice "Nice stuff !" 
--debug -param1 value1 --param2Alone /param3:"Test-:-work" /param4=--value4-- -param5 "--=nice=--"
/"param6 with spaces"="Spaces are A-OK!"

Will result in an easily accesible set of values as follows...

Command Line Arguments:

1. [size] == [100]
2. [height] == [400]
3. [day] == [happy birthday] //Complex value with spaces in the value
4. [tgif] == [Thank God It's Friday] //Complex value with spaces & apostrophe (special characters) in the value
5. [AmINice] == [Nice stuff !]
6. [debug] == [true] //Boolean flag if a standalone param key is defined
7. [param1] == [value1]
8. [param3] == [Test-:-work] //Complex value with colon (special characters) in the value
9. [param2Alone] == [true] //Boolean flag if a standalone param key is defined
10. [param4] == [--value4--] //Complex value with dashes (special characters) in the value
11. [param5] == [--=nice=--] //Complex value with equal sign (special characters) in the value
12. [param6 with spaces] == [Spaces are A-OK!] //Complex Keys or Values that have spaces

Sample Code to dynamically print all args:

    var commandLineArgHelper = new CommandLineArgsHelper(args);
    var x = 0;
    foreach (var arg in commandLineArgHelper.Parameters)
    {
        Console.WriteLine($"{++x}) [{arg.Key}] == [{arg.Value}]");
    }

Strongly Typed class Argument Example:

NOTE: This is available in the sample console app, to provide an example of how a lightweight class can provide strongly typed validate if that is desired. The code can be streamlined with the use of null-coalesce operator (or helper methods) as needed.

    /// <summary>
    /// Sample of a mapping into a Strongly Typed Command Arg class for pre-defined args that you would like to validate this way.
    /// </summary>
    public class MyCommandArgs
    {
        private CommandLineArgsHelper args = null;

        public MyCommandArgs(CommandLineArgsHelper args)
        {
            this.args = args ?? throw new ArgumentNullException(nameof(args), "Command Line Parameters collection must be specified.");
        }

        public string Size => args["size"] ?? throw new ArgumentNullException("size", "The Size argument is Required!"); //Manual Required field via Null-Coalesce
        public string Height => args["height"] ?? String.Empty; //Optional; default is empty string.
        public string Day => args["day"]; //Optional; default is null
        public string Tgif => args["tgif"].AssertArgumentNotNull("tgif"); //Required Parameter using Custom Extension Method.
        public string AmINice => args["AmINice"];
        public bool Debug => String.Equals(args["debug"], "true", StringComparison.OrdinalIgnoreCase); //Boolean value that must be 'true' to be True; case-insensitive.
        public string Param1 => args["param1"];
        public string Param2Alone => args["param2Alone"];
        public string Param3 => args["param3"];
        public string Param4 => args["param4"];
        public string Param6_with_spaces => args["param 6 with spaces"];
    }

/* MIT License

Copyright (c) 2019 Brandon Bernard

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */