XString to char UTF8

Question

Hi EW,

in your tool/lib there is a function, named EwNewStringUtf8, that I can use to convert a UTF8 string to the "Object" XString.

Is ther also a function (or a way) to convert a XString in a UTF8 string (char array)?

Thank.

Gianluca Costa

Answer 1

Hello Gianluca,

the function to encode a UTF8 string from XString is actually not available. However, this enhancement is already waiting on our to-do list. For the moment you will need to implement the function by yourself. The following dummy code could help you (based on the description found here):

XChar*         src = <EmWi String>
unsigned char* dst = <buffer to store the encoded URF8>

for ( ; src && *src; src++ )
{
  XChar c = *src;

  if ( *src <= 0x007F )
    *dst++ = (unsigned char)c;
  else if ( *src <= 0x07FF )
  {
    *dst++ = (unsigned char)( c >> 6 )   | 0xA0;
    *dst++ = (unsigned char)( c & 0x3F ) | 0x80;
  }
  else if ( *src <= 0xFFFF )
  {
    *dst++ = (unsigned char)( c >> 12 ) | 0xE0;
    *dst++ = (unsigned char)(( c >> 6  ) & 0x3F ) | 0x80;
    *dst++ = (unsigned char)( c & 0x3F ) | 0x80;
  }
}

Best regards

Paul Banach

Comments

Hello Paul,

ok, thanks.

This means that XChar is in pure UNICODE (without encoding UTF8 or UTF16 or ....) and so with XChar I can manage all and only the UNICODE Plane 0. Is it right?

Best regards.

Gianluca Costa

---

Hello Gianluca,

yes. Embedded Wizards manages the strings and chars as code points from the range 0x0000 - 0xFFFF (UNICODE Plane 0). Code points above 0xFFFF are not supported.

Best regards

Paul banach