How can I share config file like appsettings.json across multiple ASP.NET CORE projects in one solution in Visual Studio 2015?

Question

I have 3 ASP.NET CORE projects in one solution and I want to share connection string information in one config file like appsettings.json across these projects.

How can I do this in Visual Studio 2015 ?

Answer 1

You can use absolute path on each project like this(I assume appsettings.json file is in the solution root directory(like global.json) ):

var settingPath = Path.GetFullPath(Path.Combine(@"../../appsettings.json")); // get absolute path
var builder = new ConfigurationBuilder()
        .SetBasePath(env.ContentRootPath)
        .AddJsonFile(settingPath);

see https://github.com/aspnet/Configuration/issues/440

Answer 2

Set the absolute path to the shared appsettings.json file.

var relativePath = @"../../The/Relative/Path";
var absolutePath = System.IO.Path.GetFullPath(relativePath);

Then use a IFileProvider like this.

var fileProvider = 
    new Microsoft.Extensions.FileProviders.PhysicalFileProvider(absolutePath);

_configuration = new ConfigurationBuilder()
    .SetBasePath(_env.ContentRootPath)
    .AddJsonFile(fileProvider, $"appsettings.json", optional: true, reloadOnChange: true)
    .Build();

Or use SetBasePath like this.

var relativePath = @"../../The/Relative/Path";
var absolutePath = System.IO.Path.GetFullPath(relativePath);

_configuration = new ConfigurationBuilder()
    .SetBasePath(absolutePath)
    .AddJsonFile($"appsettings.json", optional: true, reloadOnChange: true)
    .Build();

Both will work, though the file provider approach allows the app to use its content root as the base path for other static content. Adem's approach is also good.

Answer 3

Another option is to use user secrets and have the apps share the same app id.

As a bonus, you get the keep the connection strings outside of your app and decrease the chances that they will leak because they were pushed in source control.

Answer 4

There may be a better way to do this, but you could achieve this by adding a precompile setting to the project.json file. Something similar to:

"scripts": {
  "precompile": [ "../copycommand.bat" ]
}

Where the copycommand points to a batch command that copies your AppSettings.json file into the current directory. If you're targeting multiple platforms, you'll likely need to customise the command for each of the platforms.

Answer 5

添加一个包含 appsettings.json 文件的共享项目，该文件设置为“如果较新则复制”并从其他项目中引用。