C
C
MIME -- Convert Base64 to Binary
See more MIME Examples
Loads MIME containing a base64 body and converts it to binary. This changes the Content-Transfer-Encoding header to "binary", and the body is stored as raw unencoded bytes.The MIME file initially loaded in this example contains:
Content-Disposition: attachment; filename="starfish20.jpg" Content-Type: image/jpeg; name="starfish20.jpg" Content-Transfer-Encoding: base64 /9j/4AAQSkZJRgABAQEASABIAAD//gAmRmlsZSB3cml0dGVuIGJ5IEFkb2JlIFBob3Rvc2hvcD8g NC4w/9sAQwAQCwwODAoQDg0OEhEQExgoGhgWFhgxIyUdKDozPTw5Mzg3QEhcTkBEV0U3OFBtUVdf YmdoZz5NcXlwZHhcZWdj/9sAQwEREhIYFRgvGhovY0I4QmNjY2NjY2NjY2NjY2NjY2NjY2NjY2Nj Y2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2Nj/8IAEQgAFAAUAwERAAIRAQMRAf/EABcAAAMBAAAA AAAAAAAAAAAAAAIDBAX/xAAYAQADAQEAAAAAAAAAAAAAAAABAgMEAP/aAAwDAQACEAMQAAAB2kZY NNEijWKddfTmLgALWH//xAAbEAACAgMBAAAAAAAAAAAAAAABAgMRAAQSE//aAAgBAQABBQL0XqN+ pM2aqJGMiqFFCyg7z//EABwRAAICAgMAAAAAAAAAAAAAAAERAAIQIQMSUf/aAAgBAwEBPwHqU5aq Axx+y1tMQl4elj//xAAcEQEAAQUBAQAAAAAAAAAAAAABEQACEBIhA1H/2gAIAQIBAT8B3Bhqy7Zc enyiwmGgDhiOzj//xAAdEAABAwUBAAAAAAAAAAAAAAABAAIREBIhIkFR/9oACAEBAAY/ArZyn+Cg xtxWuJaoCnqDuin/xAAcEAABBAMBAAAAAAAAAAAAAAABABEhYRAxQVH/2gAIAQEAAT8hkEwPUUR9 DYfE4nxtRpIkBTsayuALIiuY/9oADAMBAAIAAwAAABDWPTsf/8QAGhEAAwADAQAAAAAAAAAAAAAA AAEREDFBIf/aAAgBAwEBPxC0DVPcWm+Ce4OesrkE6bjH/8QAGBEBAQEBAQAAAAAAAAAAAAAAAREA QRD/2gAIAQIBAT8QahMiOc8YgSrnTY3ELclHXn//xAAcEAEBAAIDAQEAAAAAAAAAAAABEQAhMUFx EFH/2gAIAQEAAT8Qn3igmSZSj+c4N4zapMy9IjFV98wncN2iuLFsCEbDGxQkI6RO/n//2Q==
After converting, the binary MIME looks like the following. (Note: Loading it into a text editor and saving it will corrupt the binary data by dropping bytes. Non-text binary data CANNOT be handled as if it were text without corruption.)
Chilkat C Downloads
#include <C_CkMime.h>
#include <C_CkByteData.h>
#include <C_CkFileAccess.h>
void ChilkatSample(void)
{
BOOL success;
HCkMime mime;
const char *mimeStr;
HCkByteData mimeBytes;
HCkFileAccess fac;
success = FALSE;
// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
mime = CkMime_Create();
success = CkMime_LoadMimeFile(mime,"qa_data/mime/starfish20_base64.mim");
if (success != TRUE) {
printf("%s\n",CkMime_lastErrorText(mime));
CkMime_Dispose(mime);
return;
}
// Show the MIME. We can see the body is base64 encoded.
mimeStr = CkMime_getMime(mime);
printf("%s\n",mimeStr);
// Change the Content-Transfer-Encoding to "binary"
CkMime_SetHeaderField(mime,"Content-Transfer-Encoding","binary");
// Note: Now that the MIME's body is binary (JPG image data),
// we CANNOT get the MIME as a string. We can only get it as bytes.
mimeBytes = CkByteData_Create();
success = CkMime_GetMimeBytes(mime,mimeBytes);
// We can save it to a file, and then examine it..
fac = CkFileAccess_Create();
success = CkFileAccess_WriteEntireFile(fac,"qa_data/mime/starfish20_binary.mim",mimeBytes);
if (success != TRUE) {
printf("%s\n",CkFileAccess_lastErrorText(fac));
}
else {
printf("Saved binary MIME.\n");
}
CkMime_Dispose(mime);
CkByteData_Dispose(mimeBytes);
CkFileAccess_Dispose(fac);
}