iOS开发-获取字符串所有子串的range数组

+ (NSArray*)rangesOfSubString:(NSString*)substring inString:(NSString*)string

{

    if (substring.length == 0

        || string.length == 0) {

        return nil;

    }

    NSMutableArray *rangeArray = [[NSMutableArray alloc] init];

    NSRange searchRange = NSMakeRange(0,string.length);

    NSRange foundRange;

    while (searchRange.location < string.length) {

        searchRange.length = string.length - searchRange.location;

        foundRange = [string rangeOfString:substring options:NSCaseInsensitiveSearch range:searchRange];

        if (foundRange.location != NSNotFound) {

            // found an occurrence of the substring! do stuff here

            searchRange.location = foundRange.location+foundRange.length;

            [rangeArray addObject:[NSValue valueWithRange:foundRange]];

        } else {

            // no more substring to find

            break;

        }

    }

    return rangeArray;

}