Error c2065: "idd_dialog1": Undeclared identifier

Errors c2065: "idd_dialog1": Undeclared identifiers often occur during project compilation in VC. (⊙ O ⊙ )..., Clearly defined but not defined.

Sometimes there may be a lot

Error c2065: "idd_dialog1 ":

Error c2065: "idd_dialog2 ":

Error c2065: "idd_dialog3 ":

Error c2065: "idd_dialog4 ":

Error :.................................

Annoying. Clearly defined, all resources. H files can be found. What is the reason for this?

Some solutions on the Internet will not be mentioned here. In another case, the analysis is as follows:

Maybe you have defined a new class in the project: for example, cauthority is not derived from the MFC framework, it is a completely independent New Class (it has the header file: authority. H and implementation file: authority. CPP ).

Then the problem may occur. You may need to use the class associated with idd_dialog1 in this new class. Here it is called cmydilalog (it has the header file: mydialog. h and the implementation file: mydialog. cpp)

The header file of authority. cpp includes the following:

 
# Include "stdafx. H" # include "authority. H" # include "mydialog. H"
 

The error is as follows:

Error c2065: "idd_dialog1 ":

The error occurs because the header file of the project file is not included.

If the project name is: XXX

It should be changed to the following:

 
# Include "stdafx. H" # include "XXX. H" # include "authority. H" # include "mydialog. H"
 

Now the compilation is successful.

I don't know the specific reason. Which of the following experts can tell me ......