ASP.NET Core Isdevelopment

Question

When creating a project with the dotnet cli

dotnet new Razor -o Razorpagescontacts

How do I change the environment variable to developer mode when running the application using dotnet run.

Since in the Startup.cs I have

if (env.IsDevelopment())
{
    app.UseDeveloperExceptionPage();
}
else
{
    app.UseExceptionHandler("/Error");
}

And never gets into the app.UseDeveloperExceptionPage() using the dotnet run

Answer 1

To work with different environments in . NET Core you need to name the environment in the variable ASPNETCORE_ENVIRONMENT

Command Prompt

set ASPNETCORE_ENVIRONMENT=Development

Powershell

$Env:ASPNETCORE_ENVIRONMENT = "Development"

It is worth mentioning that the changes of the environment variable through the Command line or Powershell will only be available until the window is closed.

To assign the value of this environment variable globally, you must assign the value in the Windows Environment Variables.

1. Go to Control Panel > System > Advanced System Settings

2. Click on Environment variables

3. Click on New and attribute the Name and Valor of the Environment Variable.

For more information, visit Working with Multiple Environments

Answer 2

You need to assign the value of "Development" to the ASPNETCORE_ENVIROMENT environment variable. Before running "dotnet run" run the command below:

Console of the CMD

setx ASPNETCORE_ENVIRONMENT "Development"

Powershell

$Env:ASPNETCORE_ENVIRONMENT = "Development"

Source: https://andrewlock.net/how-to-set-the-hosting-environment-in-asp-net-core/