System.RegularExpressions replace space

Question

I have a string I am parsing with static Replace as in using this: class function Replace(const Input, Pattern, Replacement: string): string; overload; static;

my string is very simple: -c ABCDE -l 3 and I'm trying to replace -c or /c: or /c= or different possible commandline paramaters. Results should be ABCDE 3 or whatever value.

my function is so: P := regexpr.Replace(Arg,'(?i)(-|/|--)(c|l)(\s|:|=)', '');

P and Arg are string variables.

Replacement pattern is nothing. As in ''

I also tried (?i)(-|/|--)(c|l)(\s*|:|=) to match more spaces but in complied application it doesn't work.

this works but doesn't handle spaces P := regexpr.Replace(Arg,'(?i)(-|/|--)(c|l)(:|=)', '');

This part: (?i) for case insensitive.

This part: (-|/|--) similar to TSysCharSet characters but takes 2 characters at a time as in -- part in expression.

This part: (c|l) for looking at my character to specify Value.

This part: (:|=) specifying to use either : or = after my character and before Value

How do I add Space to that? I tried \s also \x20 and [ ]. I also tried with character such as c:(\s) for more spaces than one: \s* none worked so far as P = -c after replacement.

BTW this expression works on RegexBuddy as it supposed to.

EDIT1: I am replacing: -c, --c, /c, /C, --C, :, =, /x20, -l, --l, --L, etc...

cmd line is: -c ABCDE -l 3 what i have after replace is ABCDE and 3

EDIT2: As Rob Kennedy pointed out in comment below Arg doesn't have the correct string as it chokes on spaces. I used ParamCount to iterate through commands. I guess I have to parse the whole line without ParamCount. Answer below is a good expression and points out to a nice site too.

EDIT3: the expression was (?i)[-\/]+(c|l)[:=\s]* that works for multiple spaces as well. Moral of the story: ParamStr and ParamCount are good tools but do not account for all possible scenarios. better to use cmdLine for the whole string and parse it manually.

Answer 1

Since Delphi mimics the regular expression classes in the .NET framework, in order to match:

• -c
• /c:
• /c=
• /l
• /l=
• --c AGBCDE (capturing --c without AGBCDE)

Use: (?i)[-\/]+(c|l)[:=\s]?

You can see a working example here: http://regex101.com/r/rS3bD7