How to set default port for ASP.NET Core in VS Code?

Question

I develop an Angular app based on ASP.NET Core and there is some settings in launchSettings.json in order to run the app with the given ports as shown below:

"profiles": {
  "IIS Express": {
      "commandName": "IISExpress",
      "launchBrowser": true,
      "environmentVariables": {
      "DOTNET_ENVIRONMENT": "Development"
    }
  },
  "EmployeeProject.WebUI": {
      "commandName": "Project",
      "launchBrowser": true,
      "applicationUrl": "http://localhost:6000;https://localhost:6001",
      "environmentVariables": {
      "DOTNET_ENVIRONMENT": "Development"
    }
  }
}

However, I heard that these settings is ignored when using VS Code and when running the frontend and backend at the same time using dotnet watch run the app starts by using random ports in every run. So, how can I make the app starts using the same ports (6000 or 6001) via dotnet run or dotnet watch run in VS Code?

Answer 1

If you want to do this the VS Code way, as long as you use F5 (or the Run > "Start Debugging" command), it's as simple as changing the launch.json file from this:

...
"env": {
    "ASPNETCORE_ENVIRONMENT": "Development"
},
...

to this:

...
"env": {
    "ASPNETCORE_ENVIRONMENT": "Development",
    "ASPNETCORE_URLS": "http://localhost:5001"
},
...

Otherwise, if you use the IIS Express profile, edit your launchSettings.json file to specify the port:

"iisSettings": {
  "iisExpress": {
    "applicationUrl": "http://localhost:6000",
  }
},
"profiles" : { ... }

Answer 2

Running from command line execute Kastrel server not IIS. In that case probably configuration appsettings.json is use. You can put in this configuration section to control port:

    "Kestrel": {
        "Endpoints": {
            "HTTP": {
                "Url": "http://localhost:6000"
            }
        }
    },