Setting optional values using NDesk.Options

Question

Using the accepted answer in Best way to parse command line arguments in C#? as your example, how can I make the 'r' or 'repeat' option only OPTIONALLY take a value and not REQUIRE it, and how can I set a default value if the value is not provided? Thanks!

score 2 · Accepted Answer · edited Apr 25 '18 at 19:34

2

Apparently you can do something like:

{ "r|repeat:", 
       "the number of {TIMES} to repeat the greeting.\n" + 
          "this must be an integer.",
        (int v) => repeat = v ?? 1 },

Where the default value is 1 if the value is not provided.

edited Apr 25 '18 at 19:34

Paul Suart

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answered Apr 02 '15 at 01:48

Wes

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In this case, one may also the null-coalescing operator and write `repeat = v ?? 1`. – fuglede Aug 12 '16 at 10:32
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if you declare v as a string you will get "r" as value, consider that – Anwar Hossain Feb 18 '18 at 16:11

Setting optional values using NDesk.Options

1 Answers1