NSString 和 UInt8 相互转换

//NSString 转 UInt8
    NSString *str = @"测试转换";
    UInt8 buff_str[1024];
    memcpy(buff_str,[str UTF8String], [str length]+1);
    NSLog(@"char = %s",buff_str);
   
    NSString *str_From_buff = [NSString stringWithCString:(char*)buff_str encoding:NSUTF8StringEncoding];

    NSLog(@"string = %@",str_From_buff);