Month: April 2012

Searching a string – do you need to start with a period?

Searching a string – do you need to start with a period?

Today I had to write some code to search for text that matched various file extensions, this should have been a no brainer of a task. But like some things that sound stupidly simple it caught me out.

If you have a string and you use the search method then when it finds something it will return the position. If it doesn’t then it will return -1. So far so good.

Now I could go into huge detail (I did, but it ended up to wordy/dull, so I just deleted it!).
So if you EVER have to search for a string and your string starts with a period ‘.’ then add a double backslash ‘\’.
If you don’t then the period will match anything! e.g. you want to match ‘.ra’ and the string contains the word brain then ‘brain’.search( ‘.ra’ ) DOES NOT return -1!

use ‘\.ra’ for correct results.

Not sure why ‘.ra’ doesn’t work, maybe it’s treating the string like a regEx, I know search can take both a string and a regEx so maybe its not looking at its type and guessing that it should be a regEx?? You can’t step into the code either to see why, so just use the \

Very annoying!

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