A symbol value can be any integer expressed in the normal manner for #define preprocessor directives. Here are some examples of symbol values:
18
4001
0x0012
-3456
Note Symbol values for resources (accelerators, bitmaps, cursors, dialog boxes, icons, menus, string tables, and version information) must be decimal numbers in the range from 0 to 32,767 (but cannot be hexadecimal). Symbol values for parts of resources (such as dialog box controls or individual strings in the string table) can be from 0 to 65,534 or from -32,768 to 32,767.
Some number ranges are used by the development environment and MFC for special purposes.
You cannot define a symbol value using other symbol strings. For example, the following symbol definition is not supported:
#define IDC_MYEDIT IDC_OTHEREDIT //not supported
You also cannot use preprocessor macros with arguments as value definitions. For example,
#define IDD_ABOUT ID(7) //not supported
is not a valid expression regardless of what ID evaluates to at compile time.
Your application may have an existing file containing symbols defined with expressions. For more information on how to include the symbols as read-only symbols, see Using Shared (Read Only) or Calculated Symbols.