ios - NSString method stringByTrimmingCharactersInSet: not trimming comma -

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• stringbytrimmingcharactersinset: not removing characters in middle of string 6 answers

i have following code removing characters strings representing numbers:

nscharacterset *characterstokeep = [nscharacterset charactersetwithcharactersinstring:@"0123456789"]; nscharacterset *characterstoberemoved = [characterstokeep invertedset];  nsstring *mystring = [dictionary objectforkey:@"mykey"]; mystring = [mystring stringbytrimmingcharactersinset:characterstoberemoved]; mystring = [mystring stringbyreplacingoccurrencesofstring:@"," withstring:@""]; 

after method stringbytrimmingcharactersinset:, characters comma removed. after call stringbyreplacingoccurencesofstring: comma removed. why isn't removed after first call?

here sample of mystring looks after each line of code:

mystring = " $9,959 " mystring = "9,959" mystring = "9959" 

i tried

nscharacterset *characterstoberemoved = [nscharacterset decimaldigitcharacterset]; 

and got same result.

stringbytrimmingcharactersinset: trims characters ends of string, not on inside.