小编gui*_*r86的帖子

我创建了一个 .net core 辅助服务，并将 IConfiguration 注入其中，以便我可以从 appsettings.json 读取属性，但每次运行该文件时，该属性都会显示为 null。但是，如果我强制 IConfiguration 通过 ConfigurationBuilder 添加 json 文件，它就可以工作。如何使用默认设置来允许 .net core 辅助服务从 appsettings 读取？

public class ImageFileWatcher : IHostedService, IDisposable
{

    private readonly ILogger _logger;
    private readonly IConfiguration _configuration;
    FileSystemWatcher _watcher;

    public ImageFileWatcher(ILogger<ImageFileWatcher> logger, IConfiguration configuration)
    {
        _logger = logger;
        _configuration = configuration;
        // IConfigurationBuilder builder = new ConfigurationBuilder()
        // .AddJsonFile("appsettings.json")
        // .AddEnvironmentVariables();
        // this._configuration = builder.Build();
    }

    public Task StartAsync(CancellationToken cancellationToken)
    {

        var watcherConfig = _configuration["WatcherConfig:filePath"];//this is where it comes up as null. …