DART

run dart in vscode

//add 'program' and the name of your dart file to launch.json, then hit f5

"configurations": [
         {
            "name": "Flutter",
            "request": "launch",
            "type": "dart",
            "program": "lib/your_class/file_name_with_main_function.dart"
        }
    ]

how to run dart code in vscode

if you have the flutter plugin just press shift + command/contrl + D and then run and debug

how to run dart file in vscode

main. dart file will show up.
Hit Ctrl + F5 to run or Run, Run without debugging.
In the Debug Console window, you will see the result.

or 

flutter run in the terminal