Add formatting overloads to HelpText.AddXXXLine(s)/Text (a la Console.WriteLine)

[ohadschn]

It would be convenient if AddPostOptionsLine(string value) and its sibling methods had formatting string (String.Format style) overloads such as AddPostOptionsLine(string format, param args[]).

This would allow code such as:

int ExitCodeSuccess = 0;
myHelpText.AddPostOptionsLine("{0} = Success", ExitCodeSuccess);

[0xced]

Is this really necessary now that C# has string interpolation?

myHelpText.AddPostOptionsLine($"{ExitCodeSuccess} = Success");

[ohadschn]

It's certainly not necessary, but it would be both convenient and consistent with similar classes such as StringBuilder.

[ericnewton76]

@ohadschn Just for clarification, I'm assuming ExitCodeSuccess is basically a constant defined somewhere, and you're trying to abstract out a "magic number"?

If so, update your orig code sample and just include that... cause i'm wondering if an actual variable here was trying to be avoided by the original implementation

[ohadschn]

@ericnewton76 I updated the code sample per your request

[nemec]

StringBuilder actually implements its own copy of String.Format so it can avoid intermediate string allocations. The only other place I've seen something like that is in logging libraries, which do it to avoid formatting when the specific log level is turned off. We don't have any issues like those, so it sounds like you're just asking for this to be implemented inside the library?

void AddPostOptionsLine(string fmt, params object[] args)
{
    AddPostOptionsLine(String.Format(fmt, args));
}

[ohadschn]

@nemec correct, just a small convenience overload

[ohadschn]

I suppose accepting (an optional) CultureInfo would be a nice touch though.

[ericnewton76]

@nemec fyi regarding String.Format, it actually uses StringBuilder's AppendFormat in the end. This was as of Net 4.0 framework I believe. http://referencesource.microsoft.com/#mscorlib/system/string.cs,2972

They modified it at some point I think for the 3.5 release, but I'm not entirely sure.

[nemec]

Ah, you're right. I even clicked through to that method in the string class but didn't realize it took me to a stringbuilder. No wonder it looked alike!