C++ Hello World Visual Studio Code

C++ Hello World Visual Studio Code Free
Hello World C Visual Studio Code

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This topic walks you through creating a Windows 10 Universal Windows Platform (UWP) 'Hello, World!' app using C++/WinRT. The app's user interface (UI) is defined using Extensible Application Markup Language (XAML).

C++/WinRT is an entirely standard modern C++17 language projection for Windows Runtime (WinRT) APIs. For more info, and more walkthroughs and code examples, see the C++/WinRT documentation. A good topic to begin with is Get started with C++/WinRT.

Build helloworld.cpp #. Next, you will create a tasks.json file to tell VS Code how to build (compile) the program. This task will invoke the Microsoft C compiler to create an executable file based on the source code. From the main menu, choose Terminal Configure Default Build Task.

Set up Visual Studio for C++/WinRT

For info about setting up Visual Studio for C++/WinRT development—including installing and using the C++/WinRT Visual Studio Extension (VSIX) and the NuGet package (which together provide project template and build support)—see Visual Studio support for C++/WinRT.

Add hello world source code file. In the File Explorer title bar, select New File and name the file helloworld.cpp. Paste in the following source code: #include #include #include using namespace std; int main vector msg 'Hello', 'C', 'World', 'from', 'VS Code', 'and the C extension!'
In this walkthrough, you create a basic, 'Hello, World'-style C program by using a text editor, and then compile it on the command line. If you'd like to try the Visual Studio IDE instead of using the command line, see Walkthrough: Working with Projects and Solutions (C) or Using the Visual Studio IDE for C Desktop Development.
// Your First C Program. In C, any line starting with // is a comment. Comments are intended for.

To download Visual Studio, see Downloads.

For an introduction to XAML, see XAML overview

Create a Blank App (HelloWorldCppWinRT)

Our first app is a 'Hello, World!' app that demonstrates some basic features of interactivity, layout, and styles.

Begin by creating a new project in Microsoft Visual Studio. Create a Blank App (C++/WinRT) project, and name it HelloWorldCppWinRT. Make sure that Place solution and project in the same directory is unchecked. Target the latest generally-available (that is, not preview) version of the Windows SDK.

In a later section of this topic, you'll be directed to build your project (but don't build until then).

About the project files

Typically, in the project folder, each .xaml (XAML markup) file has a corresponding .idl, .h, and .cpp file. Together, those files compile into a XAML page type.

You can modify a XAML markup file to create UI elements, and you can bind those elements to data sources (a task known as data binding). You modify the .h, and .cpp files (and sometimes the .idl file) to add custom logic for your XAML page—event handlers, for example.

Let's look at some of the project files.

App.idl, App.xaml, App.h, and App.cpp. These files represent your app's specialization of the Windows::UI::Xaml::Application class, which includes your app's entry point. App.xaml doesn't contain any page-specific markup, but you can add user interface element styles there, as well as any other elements that you want to be accessible from all pages. The .h and .cpp files contain handlers for various application lifecycle events. Typically, you add custom code there to initialize your app when it starts, and to perform cleanup when it's either suspended or terminated.
MainPage.idl, MainPage.xaml, MainPage.h, and MainPage.cpp. Contain the XAML markup, and implementation, for the default main (startup) page type in an app, which is the MainPage runtime class. MainPage has no navigation support, but it provides some default UI, and an event handler, to get you started.
pch.h and pch.cpp. These files represent your project's precompiled header file. In pch.h, include any header files that don't change often, and then include pch.h in other files in the project.

A first look at the code

Runtime classes

As you may know, all of the classes in a Universal Windows Platform (UWP) app written in C# are Windows Runtime types. But when you author a type in a C++/WinRT application, you can choose whether that type is a Windows Runtime type, or a regular C++ class/struct/enumeration.

Any XAML page type in your project needs to be a Windows Runtime type. So MainPage is a Windows Runtime type. Specifically, it's a runtime class. Any type that's consumed by a XAML page also needs to be a Windows Runtime type. When you're writing a Windows Runtime component, and you want to author a type that can be consumed from another app, then you'll author a Windows Runtime type. In other cases, your type can be a regular C++ type. Generally speaking, a Windows Runtime type can be consumed using any Windows Runtime language.

One good indication that a type is a Windows Runtime type is that it's defined in Microsoft Interface Definition Language (MIDL) inside an Interface Definition Language (.idl) file. Let's take MainPage as an example.

And here's the basic structure of the implementation of the MainPage runtime class, and its activation factory, as seen in MainPage.h.

For more details about whether or not you should author a runtime class for a given type, see the topic Author APIs with C++/WinRT. And for more info about the connection between runtime classes and IDL (.idl files), you can read and follow along with the topic XAML controls; bind to a C++/WinRT property. That topic walks through the process of authoring a new runtime class, the first step of which is to add a new Midl File (.idl) item to the project.

Now let's add some functionality to the HelloWorldCppWinRT project.

Step 1. Modify your startup page

In Solution Explorer, open MainPage.xaml so that you can author the controls that form the user interface (UI).

Delete the StackPanel that's in there already, as well as its contents. In its place, paste the following XAML.

This new StackPanel has a TextBlock that prompts for the user's name, a TextBox that accepts the user's name, a Button, and another TextBlock element.

Since we deleted the Button named myButton, we'll have to remove the reference to it from the code. So, in MainPage.cpp, delete the line of code inside the MainPage::ClickHandler function.

At this point, you've created a very basic Universal Windows app. To see what the UWP app looks like, build and run the app.

In the app, you can type into the text box. But clicking the button doesn't do anything yet.

Step 2. Add an event handler

In MainPage.xaml, find the Button named inputButton, and declare an event handler for its ButtonBase::Click event. The markup for the Button should now look like this.

Implement the event handler like this.

For more info, see Handle events by using delegates.

The implementation retrieves the user's name from the text box, uses it to create a greeting, and displays that in the greetingOutput text block.

Build and run the app. Type your name in the text box, and click the button. The app displays a personalized greeting.

Step 3. Style the startup page

Choose a theme

It's easy to customize the look and feel of your app. By default, your app uses resources that have a light-colored style. The system resources also include a dark theme.

To try out the dark theme, edit App.xaml, and add a value for Application::RequestedTheme.

For apps that display mostly images or video, we recommend the dark theme; for apps that contain a lot of text, we recommend the light theme. If you're using a custom color scheme, then use the theme that goes best with your app's look and feel.

Note

A theme is applied when your app starts up. It can't be changed while the app is running.

Use system styles

In this section we'll change the appearance of the text (for example, make the font size larger).

In MainPage.xaml, find the 'What's your name?' TextBlock. Set its Style property to a reference to the BaseTextBlockStyle system resource key.

BaseTextBlockStyle is the key of a resource that's defined in the ResourceDictionary in Program Files (x86)Windows Kits10DesignTimeCommonConfigurationNeutralUAP<version>Genericgeneric.xaml. Here are the property values that are set by that style.

Also in MainPage.xaml, find the TextBlock named greetingOutput. Set its Style to BaseTextBlockStyle also. If you build and run the app now, you'll see that the appearance of both text blocks has changed (for example, the font size is now larger).

Step 4. Have the UI adapt to different window sizes

C++ Hello World Visual Studio Code Free

Now we'll cause the UI to adapt dynamically to a changing window size, and so that it looks good on devices with small displays. To do this, you'll add a VisualStateManager section into MainPage.xaml. You'll define different visual states for different window sizes, and then set the properties to apply for each of those visual states.

Adjust the UI layout

Add this block of XAML as the first child element of the root StackPanel element.

Build and run the app. Notice that the UI looks the same as before until the window is resized narrower than 641 device-independent pixels (DIPs). At that point, the narrowState visual state is applied and, along with it, all of the property setters defined for that state.

The VisualState named wideState has an AdaptiveTrigger with its MinWindowWidth property set to 641. This means that the state is to be applied only when the window width is not less than the minimum of 641 DIPs. You don't define any Setter objects for this state, so it uses the layout properties that you defined in the XAML for the page content.

The second VisualState, narrowState, has an AdaptiveTrigger with its MinWindowWidth property set to 0. This state is applied when the window width is greater than 0, but less than 641 DIPs. At exactly 641 DIPs, wideState is in effect. In narrowState, you define Setter objects to change the layout properties of controls in the UI.

You reduce the left margin of the contentPanel element from 120 to 20.
You change the Orientation of the inputPanel element from Horizontal to Vertical.
You add a top margin of 4 DIPs to the inputButton element.

Hello World C Visual Studio Code

Summary

This walkthrough showed you how to add content to a Windows Universal app, how to add interactivity, and how to change the UI's appearance.

In this tutorial, you configure Visual Studio Code to use the GCC C++ compiler (g++) and GDB debugger from mingw-w64 to create programs that run on Windows.

After configuring VS Code, you will compile and debug a simple Hello World program in VS Code. This tutorial does not teach you about GCC, GDB, Mingw-w64, or the C++ language. For those subjects, there are many good resources available on the Web.

If you have any problems, feel free to file an issue for this tutorial in the VS Code documentation repository.

Prerequisites

To successfully complete this tutorial, you must do the following steps:

Install Visual Studio Code.
Install the C/C++ extension for VS Code. You can install the C/C++ extension by searching for 'c++' in the Extensions view (⇧⌘X (Windows, Linux Ctrl+Shift+X)).
Install Mingw-w64 via the SourceForge website. Click Mingw-w64 to download the Windows Mingw-w64 installer.
1. Run the installer.
2. For Architecture select x86_64 and then select Next.
3. On the Installation Folder page, use the default installation folder. Copy the location as you will need it later.
4. Select Next to start the installation.
Add the path to your Mingw-w64 bin folder to the Windows PATH environment variable by using the following steps:
1. In the Windows search bar, type 'settings' to open your Windows Settings.
2. Search for Edit environment variables for your account.
3. Choose the Path variable and then select Edit.
4. Select New and add the Mingw-w64 destination folder path to the system path. The exact path depends on which version of Mingw-w64 you have installed and where you installed it. If you used the settings above to install Mingw-w64, then add this to the path: C:Program Filesmingw-w64x86_64-8.1.0-posix-seh-rt_v6-rev0mingw64bin.
5. Select OK to save the updated PATH. You will need to reopen any console windows for the new PATH location to be available.

Check your MinGW installation

To check that your Mingw-w64 tools are correctly installed and available, open a new Command Prompt and type:

If you don't see the expected output or g++ or gdb is not a recognized command, check your installation (Windows Control Panel > Programs) and make sure your PATH entry matches the Mingw-w64 binary location where the compilers are located.

Create Hello World

From a Windows command prompt, create an empty folder called projects where you can place all your VS Code projects. Then create a sub-folder called helloworld, navigate into it, and open VS Code in that folder by entering the following commands:

The 'code .' command opens VS Code in the current working folder, which becomes your 'workspace'. As you go through the tutorial, you will see three files created in a .vscode folder in the workspace:

tasks.json (build instructions)
launch.json (debugger settings)
c_cpp_properties.json (compiler path and IntelliSense settings)

Add a source code file

In the File Explorer title bar, select the New File button and name the file helloworld.cpp.

Add hello world source code

Now paste in this source code:

Now press ⌘S (Windows, Linux Ctrl+S) to save the file. Notice how the file you just added appears in the File Explorer view (⇧⌘E (Windows, Linux Ctrl+Shift+E)) in the side bar of VS Code:

You can also enable Auto Save to automatically save your file changes, by checking Auto Save in the main File menu.

The Activity Bar on the far left lets you open different views such as Search, Source Control, and Run. You'll look at the Run view later in this tutorial. You can find out more about the other views in the VS Code User Interface documentation.

Note: When you save or open a C++ file, you may see a notification from the C/C++ extension about the availability of an Insiders version, which lets you test new features and fixes. You can ignore this notification by selecting the X (Clear Notification).

Explore IntelliSense

In your new helloworld.cpp file, hover over vector or string to see type information. After the declaration of the msg variable, start typing msg. as you would when calling a member function. You should immediately see a completion list that shows all the member functions, and a window that shows the type information for the msg object:

You can press the Tab key to insert the selected member; then, when you add the opening parenthesis, you will see information about any arguments that the function requires.

Build helloworld.cpp

Next, you'll create a tasks.json file to tell VS Code how to build (compile) the program. This task will invoke the g++ compiler to create an executable file based on the source code.

From the main menu, choose Terminal > Configure Default Build Task. In the dropdown, which will display a tasks dropdown listing various predefined build tasks for C++ compilers. Choose g++.exe build active file, which will build the file that is currently displayed (active) in the editor.

This will create a tasks.json file in a .vscode folder and open it in the editor.

Your new tasks.json file should look similar to the JSON below:

The command setting specifies the program to run; in this case that is g++. The args array specifies the command-line arguments that will be passed to g++. These arguments must be specified in the order expected by the compiler. This task tells g++ to take the active file (${file}), compile it, and create an executable file in the current directory (${fileDirname}) with the same name as the active file but with the .exe extension (${fileBasenameNoExtension}.exe), resulting in helloworld.exe for our example.

Note: You can learn more about tasks.json variables in the variables reference.

The label value is what you will see in the tasks list; you can name this whatever you like.

The 'isDefault': true value in the group object specifies that this task will be run when you press ⇧⌘B (Windows, Linux Ctrl+Shift+B). This property is for convenience only; if you set it to false, you can still run it from the Terminal menu with Tasks: Run Build Task.

Running the build

Go back to helloworld.cpp. Your task builds the active file and you want to build helloworld.cpp.
To run the build task defined in tasks.json, press ⇧⌘B (Windows, Linux Ctrl+Shift+B) or from the Terminal main menu choose Run Build Task.
When the task starts, you should see the Integrated Terminal panel appear below the source code editor. After the task completes, the terminal shows output from the compiler that indicates whether the build succeeded or failed. For a successful g++ build, the output looks something like this:
Create a new terminal using the + button and you'll have a new terminal with the helloworld folder as the working directory. Run dir and you should now see the executable helloworld.exe.
You can run helloworld in the terminal by typing helloworld.exe (or .helloworld.exe if you use a PowerShell terminal).

Note: You might need to press Enter a couple of times initially to see the PowerShell prompt in the terminal. This issue should be fixed in a future release of Windows.

Modifying tasks.json

You can modify your tasks.json to build multiple C++ files by using an argument like '${workspaceFolder}*.cpp' instead of ${file}. This will build all .cpp files in your current folder. You can also modify the output filename by replacing '${fileDirname}${fileBasenameNoExtension}.exe' with a hard-coded filename (for example '${workspaceFolder}myProgram.exe').

Debug helloworld.cpp

Next, you'll create a launch.json file to configure VS Code to launch the GDB debugger when you press F5 to debug the program.

From the main menu, choose Run > Add Configuration.. and then choose C++ (GDB/LLDB).
You'll then see a dropdown for various predefined debugging configurations. Choose g++.exe build and debug active file.

VS Code creates a launch.json file, opens it in the editor, and builds and runs 'helloworld'.

The program setting specifies the program you want to debug. Here it is set to the active file folder ${fileDirname} and active filename with the .exe extension ${fileBasenameNoExtension}.exe, which if helloworld.cpp is the active file will be helloworld.exe.

By default, the C++ extension won't add any breakpoints to your source code and the stopAtEntry value is set to false.

Change the stopAtEntry value to true to cause the debugger to stop on the main method when you start debugging.

Note: The preLaunchTask setting is used to specify task to be executed before launch. Make sure it is consistent with the tasks.json file label setting.

Start a debugging session

Go back to helloworld.cpp so that it is the active file.
Press F5 or from the main menu choose Run > Start Debugging. Before you start stepping through the source code, let's take a moment to notice several changes in the user interface:

The Integrated Terminal appears at the bottom of the source code editor. In the Debug Output tab, you see output that indicates the debugger is up and running.
The editor highlights the first statement in the main method. This is a breakpoint that the C++ extension automatically sets for you:
The Run view on the left shows debugging information. You'll see an example later in the tutorial.
At the top of the code editor, a debugging control panel appears. You can move this around the screen by grabbing the dots on the left side.

Step through the code

Now you're ready to start stepping through the code.

Click or press the Step over icon in the debugging control panel.
This will advance program execution to the first line of the for loop, and skip over all the internal function calls within the vector and string classes that are invoked when the msg variable is created and initialized. Notice the change in the Variables window on the left.
In this case, the errors are expected because, although the variable names for the loop are now visible to the debugger, the statement has not executed yet, so there is nothing to read at this point. The contents of msg are visible, however, because that statement has completed.
Press Step over again to advance to the next statement in this program (skipping over all the internal code that is executed to initialize the loop). Now, the Variables window shows information about the loop variables.
Press Step over again to execute the cout statement. (Note that as of the March 2019 release, the C++ extension does not print any output to the Debug Console until the loop exits.)
If you like, you can keep pressing Step over until all the words in the vector have been printed to the console. But if you are curious, try pressing the Step Into button to step through source code in the C++ standard library!
To return to your own code, one way is to keep pressing Step over. Another way is to set a breakpoint in your code by switching to the helloworld.cpp tab in the code editor, putting the insertion point somewhere on the cout statement inside the loop, and pressing F9. A red dot appears in the gutter on the left to indicate that a breakpoint has been set on this line.
Then press F5 to start execution from the current line in the standard library header. Execution will break on cout. If you like, you can press F9 again to toggle off the breakpoint. Mafia 2 download for mac.
When the loop has completed, you can see the output in the Integrated Terminal, along with some other diagnostic information that is output by GDB.

Set a watch

Sometimes you might want to keep track of the value of a variable as your program executes. You can do this by setting a watch on the variable.

Place the insertion point inside the loop. In the Watch window, click the plus sign and in the text box, type word, which is the name of the loop variable. Now view the Watch window as you step through the loop.
Add another watch by adding this statement before the loop: int i = 0;. Then, inside the loop, add this statement: ++i;. Now add a watch for i as you did in the previous step.
To quickly view the value of any variable while execution is paused on a breakpoint, you can hover over it with the mouse pointer.

C/C++ configurations

If you want more control over the C/C++ extension, you can create a c_cpp_properties.json file, which will allow you to change settings such as the path to the compiler, include paths, C++ standard (default is C++17), and more.

You can view the C/C++ configuration UI by running the command C/C++: Edit Configurations (UI) from the Command Palette (⇧⌘P (Windows, Linux Ctrl+Shift+P)).

This opens the C/C++ Configurations page. When you make changes here, VS Code writes them to a file called c_cpp_properties.json in the .vscode folder.

Here, we've changed the Configuration name to GCC, set the Compiler path dropdown to the g++ compiler, and the IntelliSense mode to match the compiler (gcc-x64)

Visual Studio Code places these settings in .vscodec_cpp_properties.json. If you open that file directly, it should look something like this:

You only need to add to the Include path array setting if your program includes header files that are not in your workspace or in the standard library path.

Compiler path

The extension uses the compilerPath setting to infer the path to the C++ standard library header files. When the extension knows where to find those files, it can provide features like smart completions and Go to Definition navigation.

The C/C++ extension attempts to populate compilerPath with the default compiler location based on what it finds on your system. The extension looks in several common compiler locations.

The compilerPath search order is:

First check for the Microsoft Visual C++ compiler
Then look for g++ on Windows Subsystem for Linux (WSL)
Then g++ for Mingw-w64.

If you have Visual Studio or WSL installed, you may need to change compilerPath to match the preferred compiler for your project. For example, if you installed Mingw-w64 version 8.1.0 using the i686 architecture, Win32 threading, and sjlj exception handling install options, the path would look like this: C:Program Files (x86)mingw-w64i686-8.1.0-win32-sjlj-rt_v6-rev0mingw64bing++.exe.

Next steps

Explore the VS Code User Guide.
Review the Overview of the C++ extension.
Create a new workspace, copy your .vscode JSON files to it, adjust the necessary settings for the new workspace path, program name, and so on, and start coding!