How to watch for file changes “dotnet watch” with Visual Studio ASP.NET Core

Question

I am using Visual Studio with ASP.NET Core and run the web site using just F5 or Ctrl+F5 (not using command line directly). I would like to use the \"dotnet watch\" function

Answer 1

Open launchSettings.json and add this to profiles.

  "Watch": {
    "executablePath": "C:\\Program Files\\dotnet\\dotnet.exe",
    "commandLineArgs": "watch run",
    "launchBrowser": true,
    "launchUrl": "http://localhost:5000",
    "environmentVariables": {
      "ASPNETCORE_ENVIRONMENT": "Development"
    }
  }

Open project.json and add this to tools.

"Microsoft.DotNet.Watcher.Tools": "1.0.0-preview2-final"

After restoring, we can Watch from within Visual Studio.

Answer 2

If you want to use ASP.NET 2.x or 3.x you need to change it a bit.

• The watch tool is a global tool now and you don't need to add it as a reference any longer

• The syntax is slightly different

  "Watch": {
    "executablePath": "dotnet.exe",
    "workingDirectory": "$(ProjectDir)",
    "commandLineArgs": "watch run",
    "launchBrowser": true,
    "launchUrl": "http://localhost:5000/",
    "environmentVariables": {
      "ASPNETCORE_ENVIRONMENT": "Development"
    }
  }
  

UPDATE: added "workingDirectory" and removed specific path. It's more generic now.

Answer 3

Just one little correction to @Flynn`s answer. You need to add an

"commandName": "Executable"

argument to the "Watch" profile. Also to define the urls you should define them not in the "Watch" profile, but in the profile with

"commandName": "Program"

argument (it is present in the default launchsettings.json, created by the Visual Studio project templates, so, your launchsettings.json finally looks like this:

"AnyTest.WebClient": {
  "commandName": "Project",
  "launchBrowser": true,
  "environmentVariables": {
    "ASPNETCORE_ENVIRONMENT": "Development"
  },
  "launchUrl": "",
  "applicationUrl": "https://localhost:44353;http://localhost:51895",
  "inspectUri": "{wsProtocol}://{url.hostname}:{url.port}/_framework/debug/ws-proxy?browser={browserInspectUri}"
},
"Watch": {
  "commandName": "Executable",
  "workingDirectory": "$(ProjectDir)",
  "executablePath": "dotnet.exe",
  "commandLineArgs": "watch run"
}

I kept the launchBrowser argument in the Program profile, but browser in not launched. But if this argument is present in the Executable profile, the browser is not launched too and I found no way to launch it automatically.

Answer 4

Open launchSettings.json and add this to profiles.

 "Watch": {
      "executablePath": "dotnet.exe",
      "commandLineArgs": "watch --project ..\\..\\..\\YourProject.csproj run",
      "launchBrowser": true,
      "launchUrl": "http://localhost:5000/",
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    },

Answer 5

"Watch": {
  "commandName": "Project",
  "launchBrowser": true,
  "launchUrl": "http://localhost:5000/",
  "commandLineArgs": "watch run",
  "workingDirectory": "$(ProjectDir)",
  "executablePath": "dotnet.exe",
  "environmentVariables": {
    "ASPNETCORE_ENVIRONMENT": "Development"
  }
}

This one will work and launch the browser too. It works because of the "commandName": "Project" line, which means it will be launching with the Kestrel server.