Why wont thsi mfc code work?

[ovidiucucu]

This makes sense. So how would I write strings to the document? Or highlight certain words in the document and display it to the active view?

FILE *f;
CMyDoc *pDoc=(CMyDoc *)GetActiveDocument();
f=fopen(pDoc,"wb");
char buffer[] = { 'x' , 'y' , 'z' };
fwrite (buffer , 1 , sizeof(buffer) , f);
fclose (f);
pDoc->UpdateAllViews(NULL,0,0);

Would the above code work?

That may work but makes no sense as long as you are using MFC.