Hi,
I have a set of expressions representing some formula with some parameters inside. Like:
[parameter1] * [parameter2] * [multiplier]
And many others like this.
I want to use a regular expression so that I can get a list of strings (List<string>) which will have the following inside:
[paramter1][paramter2][multiplier]I am not using regular expressions so often; if you have already used something like this I would appreciate if you can share.
Thanks!
This should do it:
\[\w+\]
Using .net:
string s = "[parameter1] * [parameter2] * [multiplier]";
MatchCollection matches = Regex.Matches(s, @"\[\w+\]");
You may want to use a capturing group here: \[(\w+)\], so you have the parameter's name on Groups[1].
The regex
\[[^]]*\]
will match anything in square brackets:
\[ the opening bracket;
[^]] anything but a closing bracket,
* repeated zero or more times;
\] the closing bracket
I'm not sure if that's what you asked for, though...
It depends on what the parameters look like.
The general form for the regular expression will be:
\[{something which matches parameter names}\]
If the parameter names can only contain letters, digits and underscores, then you will want something like:
\[\w+\]
This will match parameter names which contain at least one letter, digit or underscore. For example:
[parameter]
[parameter1]
[1st_parameter]
[10]
[a]
[_]
A more usual limitation is to accept parameter names which contain at least one letter, digit or underscore, but must start with a letter:
\[[a-zA-Z]\w*\]
Examples include:
[parameter]
[parameter1]
[first_parameter]
[a]
but it will not match:
[1st_parameter]
[10]
[_]
However, you might decide that it should match anything between square brackets, and that anything can be a parameter name (maybe you want to validate parameter names at a later stage)
\[[^]]+\]
will match anything between square brackets so long as it contains at least 1 character.
If you also want to allow empty square brackets (i.e. match []) then you will want:
\[[^]]*\]