如何从UTF-8文件中的字符位置转换为字节位置？

Question

I have UTF-8 encoded text file. I can read it by chars. Each char can be either one byte or multibyte. How can I know where one byte was readen and whet it was readen more than one byte?

Answer 1

Count the bytes while reading the char s.

For each char c :

if(c<128)
  bytesCount++;
else if (c<2048)
  bytesCount+=2;
else
  bytesCount+=3;

See also encodeing definition wikipedia URF8