problem with match collection in using zero element/ignoring last char

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I have few user inputs which I am trying to compare via MatchCollection with different patterns I have i.e

C#

string user = "\b(?:I|would|like|to|see|id|of|bought|good)\b";

but When I am matching string

C#

string pattern = "^(?=.*\bgoods?|items?|things?\b)(?=.*\bbought\b)(?=.*\bid\b)(?=.*\btest\b).*$";

MatchCollection mat = Regex.Matches(pattern , user );

foreach (var item in mat)
{
    Console.WriteLine(item.ToString());
}

When matching the two above, the match collection only yields/collects match for (id, bought) but ignores "goods" from the first block of pattern. It seems to be ignoring **?** lookahead mentioned goods?|items?|things?.

Any suggestions.

Thanks

Posted 6-Jul-14 8:36am

Member 10237446

Updated 6-Jul-14 15:01pm

George Jonsson

v2

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George Jonsson · Accepted Answer · 2014-07-06T15:37:00

Solution 1

Hi,

Change your expression to this:

C#

string pattern = "(?=.*\bgoods\b|\bitems\b|\bthings?\b)(?=.*\bbought\b)(?=.*\bid\b)(?=.*\btest\b).*";

Putting a ? after the 's' in 'things?' will catch both thing and things.

You need to have word boundaries around each word in the optional list.
(You also misspelled goods as good in your user input, but I assume you mean goods.)

Posted 6-Jul-14 15:37pm

George Jonsson

Updated 9-Jul-14 0:44am

v2

Comments

Member 10237446 9-Jul-14 5:46am

Thanks George for the solution. Could you also please guide if in your given solution there is a possibility to use Any Character or "?" so if in pattern we have .i.e. string pattern = "(?=.*\bgoods\b|\bitems\b|\bthings?\b) and some writes only "thing" (ignoring the plural s at the end), it would still match. Thanks in advance.

George Jonsson 9-Jul-14 6:43am

I recommend this page http://www.regular-expressions.info/
(?=.*\bgood?\b|\bitems\b|\bthings?\b)(?=.*\bbought\b)(?=.*\bid\b)(?=.*\btest\b).*
Putting a ? after the 's' in 'things?' will catch both thing and things.