Walkthrough: Create a traditional Windows Desktop application (C++)

This walkthrough shows how to create a traditional Windows desktop application in Visual Studio. The application you create uses the Windows API to display "Hello, Windows desktop!" in a window. You can use the code that you develop in this walkthrough as a pattern to create Windows desktop applications.

The Windows API (also known as the Win32 API, Windows Desktop API, and Windows Classic API) is a C-language-based framework for creating Windows applications. It has been used to create Windows applications for decades. More advanced and easier-to-program frameworks have been built on top of the Windows API. For example, MFC, ATL, the .NET frameworks. Even the most modern Windows Runtime code for UWP and Store apps written in C++/WinRT uses the Windows API underneath. For more information about the Windows API, see Windows API Index.

The Build the code section at the end of this document shows the complete code. This walkthrough covers the various pieces of code that go into a Windows app, but you won't code as you go because some details are omitted in the code snippets to focus on the most important parts. You can copy the complete code and paste it into your project at the end.

Prerequisites

• A computer that runs Microsoft Windows 7 or later versions. We recommend Windows 11 or later for the best development experience.
• A copy of Visual Studio. For information on how to download and install Visual Studio, see Install Visual Studio. When you run the installer, make sure that the Desktop development with C++ workload is checked. Don't worry if you didn't install this workload when you installed Visual Studio. You can run the installer again and install it now.
• A basic understanding of using the Visual Studio IDE. If you've used Windows desktop apps before, you can probably keep up. For an introduction, see Visual Studio IDE feature tour.
• An understanding of enough of the fundamentals of the C++ language to follow along. Don't worry, we don't do anything too complicated.

Create a Windows desktop project

Follow these steps to create your first Windows desktop project. Per the note at the beginning of this walkthrough, the completed code is available in the Build the code section at the end of the walkthrough. Go ahead and follow the steps to create the project, but hold off pasting the following sections of code until the end, when the complete application code is presented. Some details are omitted in the code snippets to focus on the most important parts. You can copy the complete code and paste it into your project at the end.

To simplify the explanation. To see the documentation for your preferred version of Visual Studio, use the Version selector control. It's located at the top of the table of contents on this page.

To create a Windows desktop project in Visual Studio

1. From the main menu, choose File >New >Project to open the Create a New Project dialog box.
2. At the top of the dialog, set Language to C++, set Platform to Windows, and set Project type to Desktop.
3. From the filtered list of project types, choose Windows Desktop Wizard then choose Next. In the next page, enter a name for the project, for example, DesktopApp.
4. Choose the Create button to create the project.
5. The Windows Desktop Project dialog now appears. In the Application type dropdown, make sure you select Desktop application (.exe). Since we're making a Windows application, choosing Console Application results in a project that won't build given the code we're going to use. Then, under Additional options, select Empty project. Choose OK to create the project.
6. In Solution Explorer, right-click the DesktopApp project, choose Add, and then choose New Item.

The animation shows right-clicking on the project name in Solution Explorer, choosing Add in the menu that appears, and then choosing New Item.

Your project is now created and your source file is opened in the editor.

To create a Windows desktop project in Visual Studio 2017

1. On the File menu, choose New and then choose Project.
2. In the New Project dialog box, in the left pane, expand Installed >Visual C++, then select Windows Desktop. In the middle pane, select Windows Desktop Wizard. In the Name box, type a name for the project, for example, DesktopApp. Choose OK.
3. In the Windows Desktop Project dialog, under Application type, select Windows application (.exe). Under Additional options, select Empty project. Make sure Precompiled Header isn't selected. Choose OK to create the project.
4. In Solution Explorer, right-click the DesktopApp project, choose Add, and then choose New Item.

The animation shows right-clicking on the project name in Solution Explorer, choosing Add in the menu that appeared, and then choosing New Item.

Your project is now created and your source file is opened in the editor.

To create a Windows desktop project in Visual Studio 2015

1. On the File menu, choose New and then choose Project.
2. In the New Project dialog box, in the left pane, expand Installed >Templates >Visual C++, and then select Win32. In the middle pane, select Win32 Project. In the Name box, type a name for the project, for example, DesktopApp. Choose OK.
3. On the Overview page of the Win32 Application Wizard, choose Next.
4. On the Application Settings page, under Application type, select Windows application. Under Additional options, uncheck Precompiled header, then select Empty project. Choose Finish to create the project.
5. In Solution Explorer, right-click the DesktopApp project, choose Add, and then choose New Item.

The animation shows right-clicking on the project name in Solution Explorer, choosing Add in the menu that appears, and then choosing New Item.

Your project is now created and your source file is opened in the editor.

The code

Next, learn how to create the code for a Windows desktop application in Visual Studio.

Where code starts running in a Windows desktop application

1. Just as every C application and C++ application must have a main function as its starting point, every Windows desktop application must have a WinMain function. WinMain has the following syntax.

int WINAPI WinMain( _In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _In_ LPSTR lpCmdLine, _In_ int nCmdShow ); 

Note What are all those extra words, such as WINAPI , or CALLBACK , or HINSTANCE , or _In_ ? The traditional Windows API uses typedefs and preprocessor macros extensively to abstract away some of the details of types and platform-specific code, such as calling conventions, __declspec declarations, and compiler pragmas. In Visual Studio, you can use the IntelliSense Quick Info feature to see what these typedefs and macros define. Hover your mouse over the word of interest, or select it and press Ctrl+K, Ctrl+I for a small pop-up window that contains the definition. For more information, see Using IntelliSense. Parameters and return types often use SAL Annotations to help you catch programming errors. For more information, see Using SAL Annotations to Reduce C/C++ Code Defects.

#include #include

LRESULT CALLBACK WndProc( _In_ HWND hWnd, _In_ UINT message, _In_ WPARAM wParam, _In_ LPARAM lParam ); 

Add functionality to the WinMain function

1. In the WinMain function, you need to capture some basic information about your main window. You do that by filling out a structure of type WNDCLASSEX . The structure contains information about the window such as the application icon, the background color of the window, the name to display in the title bar, among other things. Importantly, it contains a function pointer to your window procedure that handles the messages that Windows sends to your app. The following example shows a typical WNDCLASSEX structure:

WNDCLASSEX wcex; wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = CS_HREDRAW | CS_VREDRAW; wcex.lpfnWndProc = WndProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = hInstance; wcex.hIcon = LoadIcon(wcex.hInstance, IDI_APPLICATION); wcex.hCursor = LoadCursor(NULL, IDC_ARROW); wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); wcex.lpszMenuName = NULL; wcex.lpszClassName = szWindowClass; wcex.hIconSm = LoadIcon(wcex.hInstance, IDI_APPLICATION); 

if (!RegisterClassEx(&wcex))

static TCHAR szWindowClass[] = _T("DesktopApp"); static TCHAR szTitle[] = _T("Windows Desktop Guided Tour Application"); // The parameters to CreateWindowEx explained: // WS_EX_OVERLAPPEDWINDOW : An optional extended window style. // szWindowClass: the name of the application // szTitle: the text that appears in the title bar // WS_OVERLAPPEDWINDOW: the type of window to create // CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y) // 500, 100: initial size (width, length) // NULL: the parent of this window // NULL: this application does not have a menu bar // hInstance: the first parameter from WinMain // NULL: not used in this application HWND hWnd = CreateWindowEx( WS_EX_OVERLAPPEDWINDOW, szWindowClass, szTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 500, 100, NULL, NULL, hInstance, NULL ); if (!hWnd)

// The parameters to ShowWindow explained: // hWnd: the value returned from CreateWindow // nCmdShow: the fourth parameter from WinMain ShowWindow(hWnd, nCmdShow); UpdateWindow(hWnd); 

MSG msg; while (GetMessage(&msg, NULL, 0, 0)) < TranslateMessage(&msg); DispatchMessage(&msg); >return (int) msg.wParam; 

For more information about the structures and functions in the message loop, see MSG , GetMessage , TranslateMessage, and DispatchMessage . A basic WinMain function that creates the application's main window, and listens for messages that Windows sends your app, would resemble the following code:

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) < WNDCLASSEX wcex; wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = CS_HREDRAW | CS_VREDRAW; wcex.lpfnWndProc = WndProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = hInstance; wcex.hIcon = LoadIcon(wcex.hInstance, IDI_APPLICATION); wcex.hCursor = LoadCursor(NULL, IDC_ARROW); wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); wcex.lpszMenuName = NULL; wcex.lpszClassName = szWindowClass; wcex.hIconSm = LoadIcon(wcex.hInstance, IDI_APPLICATION); if (!RegisterClassEx(&wcex)) < MessageBox(NULL, _T("Call to RegisterClassEx failed!"), _T("Windows Desktop Guided Tour"), NULL); return 1; >// Store instance handle in our global variable hInst = hInstance; // The parameters to CreateWindowEx explained: // WS_EX_OVERLAPPEDWINDOW : An optional extended window style. // szWindowClass: the name of the application // szTitle: the text that appears in the title bar // WS_OVERLAPPEDWINDOW: the type of window to create // CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y) // 500, 100: initial size (width, length) // NULL: the parent of this window // NULL: this application dows not have a menu bar // hInstance: the first parameter from WinMain // NULL: not used in this application HWND hWnd = CreateWindowEx( WS_EX_OVERLAPPEDWINDOW, szWindowClass, szTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 500, 100, NULL, NULL, hInstance, NULL ); if (!hWnd) < MessageBox(NULL, _T("Call to CreateWindow failed!"), _T("Windows Desktop Guided Tour"), NULL); return 1; >// The parameters to ShowWindow explained: // hWnd: the value returned from CreateWindow // nCmdShow: the fourth parameter from WinMain ShowWindow(hWnd, nCmdShow); UpdateWindow(hWnd); // Main message loop: MSG msg; while (GetMessage(&msg, NULL, 0, 0)) < TranslateMessage(&msg); DispatchMessage(&msg); >return (int) msg.wParam; > 

Handle messages in the WndProc function

1. To handle messages that the application receives, you implement a switch statement in your WndProc function. An important message to handle is WM_PAINT . The application receives a WM_PAINT message when part of its displayed window must be updated. The event can occur when a user moves a window in front of your window and moves it away again. It receives this message the first time your window is displayed, giving you a chance to display your application UI. Your application finds out about these events when Windows sends them. When the window is first displayed, all of it must be updated. To handle a WM_PAINT message, first call BeginPaint , then handle all the logic to lay out the text, buttons, and other controls in the window. Then call EndPaint . For this application, the code between BeginPaint() and EndPaint() displays Hello, Windows desktop! in the window you created in WinMain() . In the following code, the TextOut function displays the text at the specified location in the window.

PAINTSTRUCT ps; HDC hdc; TCHAR greeting[] = _T("Hello, Windows desktop!"); switch (message) < case WM_PAINT: hdc = BeginPaint(hWnd, &ps); // Here your application is laid out. // For this introduction, we just print out "Hello, Windows desktop!" // in the top left corner. TextOut(hdc, 5, 5, greeting, _tcslen(greeting)); // End application-specific layout section. EndPaint(hWnd, &ps); break; >

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) < PAINTSTRUCT ps; HDC hdc; TCHAR greeting[] = _T("Hello, Windows desktop!"); switch (message) < case WM_PAINT: hdc = BeginPaint(hWnd, &ps); // Here your application is laid out. // For this introduction, we just print out "Hello, Windows desktop!" // in the top left corner. TextOut(hdc, 5, 5, greeting, _tcslen(greeting)); // End application specific layout section. EndPaint(hWnd, &ps); break; case WM_DESTROY: PostQuitMessage(0); break; default: return DefWindowProc(hWnd, message, wParam, lParam); break; >return 0; > 

Build the code

As promised, the complete code for the working application follows.

To build this example

1. Delete all the code in HelloWindowsDesktop.cpp in the editor. Copy this example code and paste it into HelloWindowsDesktop.cpp:

// HelloWindowsDesktop.cpp // compile with: /D_UNICODE /DUNICODE /DWIN32 /D_WINDOWS /c #include #include #include #include // Global variables // The main window class name. static TCHAR szWindowClass[] = _T("DesktopApp"); // The string that appears in the application's title bar. static TCHAR szTitle[] = _T("Windows Desktop Guided Tour Application"); // Stored instance handle for use in Win32 API calls such as FindResource HINSTANCE hInst; // Forward declarations of functions included in this code module: LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM); int WINAPI WinMain( _In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _In_ LPSTR lpCmdLine, _In_ int nCmdShow ) < WNDCLASSEX wcex; wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = CS_HREDRAW | CS_VREDRAW; wcex.lpfnWndProc = WndProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = hInstance; wcex.hIcon = LoadIcon(wcex.hInstance, IDI_APPLICATION); wcex.hCursor = LoadCursor(NULL, IDC_ARROW); wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); wcex.lpszMenuName = NULL; wcex.lpszClassName = szWindowClass; wcex.hIconSm = LoadIcon(wcex.hInstance, IDI_APPLICATION); if (!RegisterClassEx(&wcex)) < MessageBox(NULL, _T("Call to RegisterClassEx failed!"), _T("Windows Desktop Guided Tour"), NULL); return 1; >// Store instance handle in our global variable hInst = hInstance; // The parameters to CreateWindowEx explained: // WS_EX_OVERLAPPEDWINDOW : An optional extended window style. // szWindowClass: the name of the application // szTitle: the text that appears in the title bar // WS_OVERLAPPEDWINDOW: the type of window to create // CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y) // 500, 100: initial size (width, length) // NULL: the parent of this window // NULL: this application does not have a menu bar // hInstance: the first parameter from WinMain // NULL: not used in this application HWND hWnd = CreateWindowEx( WS_EX_OVERLAPPEDWINDOW, szWindowClass, szTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 500, 100, NULL, NULL, hInstance, NULL ); if (!hWnd) < MessageBox(NULL, _T("Call to CreateWindow failed!"), _T("Windows Desktop Guided Tour"), NULL); return 1; >// The parameters to ShowWindow explained: // hWnd: the value returned from CreateWindow // nCmdShow: the fourth parameter from WinMain ShowWindow(hWnd, nCmdShow); UpdateWindow(hWnd); // Main message loop: MSG msg; while (GetMessage(&msg, NULL, 0, 0)) < TranslateMessage(&msg); DispatchMessage(&msg); >return (int) msg.wParam; > // FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM) // // PURPOSE: Processes messages for the main window. // // WM_PAINT - Paint the main window // WM_DESTROY - post a quit message and return LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) < PAINTSTRUCT ps; HDC hdc; TCHAR greeting[] = _T("Hello, Windows desktop!"); switch (message) < case WM_PAINT: hdc = BeginPaint(hWnd, &ps); // Here your application is laid out. // For this introduction, we just print out "Hello, Windows desktop!" // in the top left corner. TextOut(hdc, 5, 5, greeting, _tcslen(greeting)); // End application-specific layout section. EndPaint(hWnd, &ps); break; case WM_DESTROY: PostQuitMessage(0); break; default: return DefWindowProc(hWnd, message, wParam, lParam); break; >return 0; > 

The animation shows clicking the save all button, then choosing Build > Build Solution from the main menu.

Congratulations! You've built a traditional Windows desktop application.