ios 开发 截取2个指定字符串之间的字符

iOS  截取字符串中2个指定字符串之间的字符串

   NSString *resourceString = @"=需要截取的字符串+";

    NSRange start = [resourceString rangeOfString:@"="];

    NSRange end = [resourceString rangeOfString:@"+"];

    NSRange range = NSMakeRange(start.location + start.length, end.location - start.location - start.length);

    NSString *result = [resourceString substringWithRange:range];

    NSLog(@"%@",result);