Run C++ Code In Visual Studio Code

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  1. Visual Studio Code C++ Compiler
  2. How To Run My C++ Code In Visual Studio Code
  3. Visual Studio Code C++ Build
  4. How To Run C++ Code In Visual Studio Code

Install Visual Studio Code. Install the 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)). Ensure GCC is installed. Although you'll use VS Code to edit your source code, you'll. Run C/C program in visual studio code on windows operating system.Hey, guys in this video I'm going to show you how you can configure visual studio code (#. You can configure multiple tasks in Visual Studio Code, one of which will allow you to build your executable, and the other will run your executable. Optionally, you could also look into Visual Studio Code's 'Run Mode' (see here). If you use 'Run Mode', you should be able to configure Visual Studio Code to build your executable, and then launch it. VSC – C/C Extension download. Now your VS code is ready to compile and run C/C code but also to obtain output in one click, We need another extension. Here, We have picked Code Runner Extension. You can download this extension from the extension center or click here to install. VSC – Code Runner Extension Download.

In this tutorial, you will configure Visual Studio Code to use the GCC C++ compiler (g++) and GDB debugger on Linux. GCC stands for GNU Compiler Collection; GDB is the GNU debugger.

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

If you have trouble, 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:

  1. Install Visual Studio Code.

  2. Install the 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)).

Ensure GCC is installed

Although you'll use VS Code to edit your source code, you'll compile the source code on Linux using the g++ compiler. You'll also use GDB to debug. These tools are not installed by default on Ubuntu, so you have to install them. Fortunately, that's easy.

First, check to see whether GCC is already installed. To verify whether it is, open a Terminal window and enter the following command:

If GCC isn't installed, run the following command from the terminal window to update the Ubuntu package lists. An out-of-date Linux distribution can sometimes interfere with attempts to install new packages.

Next install the GNU compiler tools and the GDB debugger with this command:

Create Hello World

From the terminal window, create an empty folder called projects to store your VS Code projects. Then create a subfolder 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 create three files in a .vscode folder in the workspace:

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

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:

Now press ⌘S (Windows, Linux Ctrl+S) to save the file. Notice that your files are listed 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.

Visual Studio Code C++ Compiler

The Activity Bar on the edge of Visual Studio Code 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 the 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'll see information about 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 from the source code.

It's important to have helloworld.cpp open in the editor because the next step uses the active file in the editor for context to create the build task in the next step.

From the main menu, choose Terminal > Configure Default Build Task. A dropdown appears showing various predefined build tasks for C++ compilers. Choose C/C++: g++ build active file.

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:

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

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 without an extension (${fileBasenameNoExtension}), resulting in helloworld for our example.

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

  1. Go back to helloworld.cpp. Your task builds the active file and you want to build helloworld.cpp.

  2. 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.

  3. 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:

  4. Create a new terminal using the + button and you'll have a terminal running your default shell with the helloworld folder as the working directory. Run ls and you should now see the executable helloworld (no file extension).

  5. You can run helloworld in the terminal by typing ./helloworld.

Modifying tasks.json

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

How To Run My C++ Code In Visual Studio Code

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++ build and debug active file.

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

In the JSON above, program specifies the program you want to debug. Here it is set to the active file folder ${fileDirname} and active filename without an extension ${fileBasenameNoExtension}, which if helloworld.cpp is the active file will be helloworld.

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.

Start a debugging session

  1. Go back to helloworld.cpp so that it is the active file.
  2. Press F5 or from the main menu choose Run > Start Debugging. Before you start stepping through the code, let's take a moment to notice several changes in the user interface:
How to run c code in visual studio code 2017

  • 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.

  1. 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 side.

  2. 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.

  3. 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 last cout executes.)

  4. 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.

    When the loop has completed, you can see the output in the Debug Console tab of the integrated terminal, along with some other diagnostic information that is output by GDB.

Set a watch

To keep track of the value of a variable as your program executes, set a watch on the variable.

  1. 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.

  2. 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.

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

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

Reusing your C++ configuration

VS Code is now configured to use gcc on Linux. The configuration applies to the current workspace. To reuse the configuration, just copy the JSON files to a .vscode folder in a new project folder (workspace) and change the names of the source file(s) and executable as needed.

Troubleshooting

Compiler and linking errors

The most common cause of errors (such as undefined _main, or attempting to link with file built for unknown-unsupported file format, and so on) occurs when helloworld.cpp is not the active file when you start a build or start debugging. This is because the compiler is trying to compile something that isn't source code, like your launch.json, tasks.json, or c_cpp_properties.json file.

Next steps

  • Explore the VS Code User Guide.
  • Review the Overview of the C++ extension.
  • Create a new workspace, copy your .json files to it, adjust the necessary settings for the new workspace path, program name, and so on, and start coding!
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This article introduces the features of the Visual Studio debugger in a step-by-step walkthrough. If you want a higher-level view of the debugger features, see First look at the debugger. When you debug your app, it usually means that you are running your application with the debugger attached. When you do this, the debugger provides many ways to see what your code is doing while it runs. You can step through your code and look at the values stored in variables, you can set watches on variables to see when values change, you can examine the execution path of your code, see whether a branch of code is running, and so on. If this is the first time that you've tried to debug code, you may want to read Debugging for absolute beginners before going through this article.

Although the demo app is C++, most of the features are applicable to C#, Visual Basic, F#, Python, JavaScript, and other languages supported by Visual Studio (F# does not support Edit-and-continue. F# and JavaScript do not support the Autos window). The screenshots are in C++.

In this tutorial, you will:

  • Start the debugger and hit breakpoints.
  • Learn commands to step through code in the debugger
  • Inspect variables in data tips and debugger windows
  • Examine the call stack

Prerequisites

You must have Visual Studio 2019 installed and the Desktop development with C++ workload.

You must have Visual Studio 2017 installed and the Desktop development with C++ workload.

If you haven't already installed Visual Studio, go to the Visual Studio downloads page to install it for free.

If you haven't already installed Visual Studio, go to the Visual Studio downloads page to install it for free.

If you need to install the workload but already have Visual Studio, go to Tools > Get Tools and Features.., which opens the Visual Studio Installer. The Visual Studio Installer launches. Choose the Desktop development with C++ workload, then choose Modify.

Create a project

First, you'll create a C++ console application project. The project type comes with all the template files you'll need, before you've even added anything!

  1. Open Visual Studio 2017.

  2. From the top menu bar, choose File > New > Project.

  3. In the New Project dialog box in the left pane, expand Visual C++ and then choose Windows Desktop. In the middle pane, choose Windows Console Application. Then name the project get-started-debugging.

    If you don't see the Console App project template, choose the Open Visual Studio Installer link in the left pane of the New Project dialog box. The Visual Studio Installer launches. Choose the .NET Core cross-platform development workload, and then choose Modify.

  4. Click OK.

    Visual Studio opens your new project.

  1. Open Visual Studio 2019.

    If the start window is not open, choose File > Start Window.

  2. On the start window, choose Create a new project.

  3. On the Create a new project window, enter or type console in the search box. Next, choose C++ from the Language list, and then choose Windows from the Platform list.

    After you apply the language and platform filters, choose the Console App template, and then choose Next.

    Note

    If you do not see the Console App template, you can install it from the Create a new project window. In the Not finding what you're looking for? message, choose the Install more tools and features link. Then, in the Visual Studio Installer, choose the Desktop development with C++ workload.

  4. In the Configure your new project window, type or enter get-started-debugging in the Project name box. Then, choose Create.

    Visual Studio opens your new project.

Create the application

  1. In get-started-debugging.cpp, replace all of the default code with the following code instead:

Start the debugger!

  1. Press F5 (Debug > Start Debugging) or the Start Debugging button in the Debug Toolbar.

    F5 starts the app with the debugger attached to the app process, but right now we haven't done anything special to examine the code. So the app just loads and you see the console output.

    In this tutorial, we'll take a closer look at this app using the debugger and get a look at the debugger features.

  2. Stop the debugger by pressing the red stop button (Shift + F5).

  3. In the console window, press a key and Enter to close the console window.

Set a breakpoint and start the debugger

  1. In the for loop of the main function, set a breakpoint by clicking the left margin of the following line of code:

    name += letters[i];

    A red circle appears where you set the breakpoint.

    Breakpoints are one of the most basic and essential features of reliable debugging. A breakpoint indicates where Visual Studio should suspend your running code so you can take a look at the values of variables, or the behavior of memory, or whether or not a branch of code is getting run.

  2. Press F5 or the Start Debugging button , the app starts, and the debugger runs to the line of code where you set the breakpoint.

    The yellow arrow represents the statement on which the debugger paused, which also suspends app execution at the same point (this statement has not yet executed).

    If the app is not yet running, F5 starts the debugger and stops at the first breakpoint. Otherwise, F5 continues running the app to the next breakpoint.

    Breakpoints are a useful feature when you know the line of code or the section of code that you want to examine in detail. For information on the different types of breakpoints you can set, such as conditional breakpoints, see Using breakpoints.

Navigate code in the debugger using step commands

Mostly, we use the keyboard shortcuts here, because it's a good way to get fast at executing your app in the debugger (equivalent commands such as menu commands are shown in parentheses).

  1. While paused in the for loop in the main method, press F11 (or choose Debug > Step Into) twice to to advance to the SendMessage method call.

    After pressing F11 twice, you should be at this line of code:

    SendMessage(name, a[i]);

  2. Press F11 one more time to step into the SendMessage method.

    The yellow pointer advances into the SendMessage method.

    F11 is the Step Into command and advances the app execution one statement at a time. F11 is a good way to examine the execution flow in the most detail. (To move faster through code, we show you some other options also.) By default, the debugger skips over non-user code (if you want more details, see Just My Code).

    Let's say that you are done examining the SendMessage method, and you want to get out of the method but stay in the debugger. You can do this using the Step Out command.

  3. Press Shift + F11 (or Debug > Step Out).

    This command resumes app execution (and advances the debugger) until the current method or function returns.

    You should be back in the for loop in the main method, paused at the SendMessage method call.

  4. Press F11 several times until you get back to the SendMessage method call again.

  5. While paused at the method call, press F10 (or choose Debug > Step Over) once.

    Notice this time that the debugger does not step into the SendMessage method. F10 advances the debugger without stepping into functions or methods in your app code (the code still executes). By pressing F10 on the SendMessage method call (instead of F11), we skipped over the implementation code for SendMessage (which maybe we're not interested in right now). For more information on different ways to move through your code, see Navigate code in the debugger.

Navigate code using Run to Click

  1. Press F5 to advance to the breakpoint.

  2. In the code editor, scroll down and hover over the std::wcout function in the SendMessage method until the green Run to Click button appears on the left. The tooltip for the button shows 'Run execution to here'.

    Note

    The Run to Click button is new in Visual Studio 2017. (If you don't see the green arrow button, use F11 in this example instead to advance the debugger to the right place.)

  3. Click the Run to Click button .

    The debugger advances to the std::wcout function.

    Using this button is similar to setting a temporary breakpoint. Run to Click is handy for getting around quickly within a visible region of app code (you can click in any open file).

Restart your app quickly

Click the Restart button in the Debug Toolbar (Ctrl + Shift + F5).

When you press Restart, it saves time versus stopping the app and restarting the debugger. The debugger pauses at the first breakpoint that is hit by executing code.

Visual Studio Code C++ Build

The debugger stops again at the breakpoint you previously set inside the for loop.

Inspect variables with data tips

Features that allow you to inspect variables are one of the most useful features of the debugger, and there are different ways to do it. Often, when you try to debug an issue, you are attempting to find out whether variables are storing the values that you expect them to have at a particular time.

How To Run C++ Code In Visual Studio Code

  1. While paused on the name += letters[i] statement, hover over the letters variable and you see it's default value, size={10}.

  2. Expand the letters variable to see its properties, which include all the elements that the variable contains.

  3. Next, hover over the name variable, and you see its current value, an empty string.

  4. Press F5 (or Debug > Continue) a few times to iterate several times through the for loop, pausing again at the breakpoint, and hovering over the name variable each time to check its value.

    The value of the variable changes with each iteration of the for loop, showing values of f, then fr, then fre, and so on.

    Often, when debugging, you want a quick way to check property values on variables, to see whether they are storing the values that you expect them to store, and the data tips are a good way to do it.

Inspect variables with the Autos and Locals windows

  1. Look at the Autos window at the bottom of the code editor.

    If it is closed, open it while paused in the debugger by choosing Debug > Windows > Autos.

    In the Autos window, you see variables and their current value. The Autos window shows all variables used on the current line or the preceding line (Check documentation for language-specific behavior).

  2. Next, look at the Locals window, in a tab next to the Autos window.

  3. Expand the letters variable to show the elements that it contains.

    The Locals window shows you the variables that are in the current scope, that is, the current execution context.

Set a watch

  1. In the main code editor window, right-click the name variable and choose Add Watch.

    The Watch window opens at the bottom of the code editor. You can use a Watch window to specify a variable (or an expression) that you want to keep an eye on.

    Now, you have a watch set on the name variable, and you can see its value change as you move through the debugger. Unlike the other variable windows, the Watch window always shows the variables that you are watching (they're grayed out when out of scope).

Examine the call stack

  1. While paused in the for loop, click the Call Stack window, which is by default open in the lower right pane.

    If it is closed, open it while paused in the debugger by choosing Debug > Windows > Call Stack.

  2. Click F11 a few times until you see the debugger pause in the SendMessage method. Look at the Call Stack window. To mp3 converter free.

    The Call Stack window shows the order in which methods and functions are getting called. The top line shows the current function (the SendMessage method in this app). The second line shows that SendMessage was called from the main method, and so on.

    Note

    The Call Stack window is similar to the Debug perspective in some IDEs like Eclipse.

    The call stack is a good way to examine and understand the execution flow of an app.

    You can double-click a line of code to go look at that source code and that also changes the current scope being inspected by the debugger. This action does not advance the debugger.

    You can also use right-click menus from the Call Stack window to do other things. For example, you can insert breakpoints into specified functions, advance the debugger using Run to Cursor, and go examine source code. For more information, see How to: Examine the Call Stack.

Change the execution flow

  1. Press F11 twice to run the std::wcout function.

  2. With the debugger paused in the SendMessage method call, use the mouse to grab the yellow arrow (the execution pointer) on the left and move the yellow arrow up one line, back to std::wcout.

  3. Press F11.

    The debugger reruns the std::wcout function (you see this in the console window output).

    By changing the execution flow, you can do things like test different code execution paths or rerun code without restarting the debugger.

    Warning

    Often you need to be careful with this feature, and you see a warning in the tooltip. You may see other warnings, too. Moving the pointer cannot revert your application to an earlier app state.

  4. Press F5 to continue running the app.

    Congratulations on completing this tutorial!

Next steps

In this tutorial, you've learned how to start the debugger, step through code, and inspect variables. You may want to get a high-level look at debugger features along with links to more information.