Question

Here i do a regular expression where _pattern is the list of teams and _name is the keyword i would like to find whether it matches the _pattern.

Result shows that it matched. I’m wondering why is it possible because the keyword is totally different to the _pattern. I suspect that it is related with the é symbol.

string _pattern = "Ipswich Town F.C.|Ipswich Town Football Club|Ipswich|The Blues||Town|The Tractor Boys|Ipswich Town";
string _name = "Estudiantes de Mérida";
regex = new Regex( @"(" + _pattern + @")", RegexOptions .IgnoreCase );

Match m = regex. Match (_name );
if (m . Success)
{
   var g = m. Groups [1 ]. Value;
   break ;
}

Answer 1

It has nothing to do with the é symbol. Let’s go over a few things..

Is it right that there are 2 | in as your questions formulates :

The Blues||Town

Also the point has special meaning in a regex so you should escape it

meaIpswich Town F\.C\.

And alternatives should be enclosed with parenthesis:

(Ipswich Town F.C.)|(Ipswich Town Football Club)|(Ipswich)|

The parenthesis in the following java line are not necessary

regex = new Regex( @"(" + _pattern + @")"

Aneway, The reason that it matches is not do to a valid regex. I think it has to do with your use of the java API.

The regex that I would rewrite for your purposes is:

^((Ipswich Town F\.C\.)|(Ipswich Town Football Club)|(Ipswich)|(The Blues)|(Town)|(The Tractor Boys)|(Ipswich Town))$

As you can see, there are quit a few differences.