String Encoding and decoding in iOS

- (NSString *)stringByURLDecode {
   
    NSMutableString *tempStr = [NSMutableString stringWithString:self];
    [tempStr replaceOccurrencesOfString:@"+" withString:@" " options:NSCaseInsensitiveSearch range:NSMakeRange(0, [tempStr length])];
   
    return [[NSString stringWithFormat:@"%@",tempStr] stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
   
}




- (NSString *)stringByURLEncode {
   
    NSMutableString *tempStr = [NSMutableString stringWithString:self];
    [tempStr replaceOccurrencesOfString:@" " withString:@"+" options:NSCaseInsensitiveSearch range:NSMakeRange(0, [tempStr length])];
   
   
    return [[NSString stringWithFormat:@"%@",tempStr] stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
   
}