In ASP.NET Core, the launchSettings.json file is a configuration file that allows you to define various settings related to launching and debugging your application during development. It provides a centralized place to configure how your application is launched and provides options for different environments and profiles.

The launchSettings.json file is typically located in the “Properties” folder of the project and is used by development tools like Visual Studio or the .NET CLI to determine how the application should be launched and what settings should be applied.

Here are some common settings that can be configured in the launchSettings.json file:

Profiles: The file supports multiple profiles, each representing a specific way to launch or debug the application. For example, you can have profiles for different environments like “Development,” “Staging,” or “Production,” each with its own set of configuration options.

Application URL: You can specify the URL on which the application should listen when launched. This is useful when you want to override the default URL or when you need to configure different URLs for different profiles.

Environment variables: The launchSettings.json file allows you to define environment variables specific to each profile. This can be useful when you need to provide different settings or configuration values based on the profile being used.

Command-line arguments: You can specify command-line arguments to be passed when launching the application for each profile. This is helpful if your application requires specific command-line arguments during development or debugging.

Debugging settings: The launchSettings.json file also includes options for configuring the debugging experience, such as the type of debugger to use, the launch browser, and other debugging-related settings.

By using the launchSettings.json file, you can define different launch configurations and easily switch between them during development. It provides flexibility and convenience when launching and debugging your ASP.NET Core application, allowing you to customize the environment, URL, command-line arguments, and other settings based on your needs.