Win32API Interview Preparation Guide
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Win32API frequently Asked Questions by expert members with experience in Win32API. So get preparation for the Win32API job interview

20 Win32API Questions and Answers:

1 :: What is Win32?

Win32 refers to Microsoft 32 bit Windows API. Win32
Applications are programs which are built with the Win32

2 :: What is Function entry for DLL in win3.1?

Should be LibMain in win3.1

3 :: What is System call executable binary file into a process?

But WinExec() is compatible with 16-bit Windows.
Applications should use the CreateProcess

4 :: win 3.1 supports which type of multi tasking?

Win3.1 supports co-operative multi-tasking. Once a process
is given the control for execution, the other tasks have to
wait until the current has relinquished its execution.

WinNT is preemptive multi-tasking. A process can be stopped
in the middle if another process needs CPU cycle.
This is handled by the windows OS.

5 :: What are the COM components?

It evolved like this
when u write a CLASS to reuse in a application, multiple
intances of the class exists with each instance of
Next u want to avoid it so u make a class and put it in DLL
now only one instance exists though multiple instances of
applications exists
Applicatoin needs to be recompiled whenever Dll is
modified, SO came COM.
COM is independent component that internally handles
networking, resources etc, COM uses IDL to communicate to
different languages

6 :: How to Initialize contents of a dialog?

In MFC, the contents of a dialog are initialized if they are
associated with their corresponding data members. This is
done through "UpdateData(FALSE)" function. The control data
is transferred to the data members through "UpdateData(TRUE)".

In WIN32, the dialog data in controls can be initialized
during WM_INITDIALOG call. The control data can be updated
to the dialog members using apppropriate "SendMessage"

7 :: What is the difference between MFC and Win32?

Win32 is a set of Windows APIs written in C and MFC is a
framework built arround Win32. All MFC functions internally
use Win32 APIs. And MFC is written in C++.

8 :: What are the design patterns of an MFC application?

It uses main three patterns,
Singleton pattern - Application object(CWinApp & its
derived classes)
Bridge pattern - Serialization
Observer patten - Document/View Architecture

If we dig deeper into the MFC classes, it may use some
other patterns also.

9 :: In Win32 application can we use CString datatype?

A faik CString is a MFC class. You cannot use it in win32
application unless you set your application to use MFC
libraries. To use MFC in win32 application, go to project
settings and in general tab, set it to use MFC libraries in
shared DLL. Then you can include MFC framework files like

10 :: What API used to hide window?

ShowWindow(hwnd, SW_HIDE); // to hide window
ShowWindow(hwnd, SW_SHOW); // to show window