Archive for April, 2009

Here is a little tip on how to tell if a string contains another string, using the underused data type NSRange.

NSRange gives the starting location and the length of a given value, and is often used with arrays and strings. On this occasion we will use it to find the range of a substring within another string. If the range has a location, it contains the given substring. The following code does just that.

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NSRange textRange;
textRange =[string rangeOfString:substring];
 
if(textRange.location != NSNotFound)
{
 
//Does contain the substring
}

Making this a case insensitive compare is also very trivial, and can be done by lowercasing both strings

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NSRange textRange;
textRange =[[string lowercaseString] rangeOfString:[substring lowercaseString]];
 
if(textRange.location != NSNotFound)
{
 
//Does contain the substring
 
}