如何在Core 2.0中的ConfigurationBuilder中设置SetPath

如何在Core 2.0的ConfigurationBuilder中设置基本路径。

我用Google搜索，发现这个问题，这个来自微软的文档，以及2.0文档在线，但他们似乎使用的版本Microsoft.Extension.Configuration从1.0.0-beta8。

我想读appsettings.json。在Core 2.0中，有没有新的方法可以做到这一点？

using System;
using System.IO;
using Microsoft.Extensions.Configuration;
namespace ConsoleApp2
{
    class Program
    {
        public static IConfigurationRoot Configuration { get; set; }

        static void Main(string[] args)
        {
            var builder = new ConfigurationBuilder()
                .SetBasePath(Directory.GetCurrentDirectory()) // <== compile failing here
                .AddJsonFile("appsettings.json");

            Configuration = builder.Build();

            Console.WriteLine(Configuration.GetConnectionString("con"));
            Console.WriteLine("Press a key...");
            Console.ReadKey();
        }
    }
}

appsetting.json

{
  "ConnectionStrings": {
    "con": "connection string"
  }
}

更新： 除了按照Set指示的那样添加Microsoft.Extensions.Configuration.FileExtensions，我还需要添加Microsoft.Extensions.Configuration.Json来获取扩展名。AddJsonFile

该SetBasePath扩展方法中定义Config.FileExtensions。

您需要添加对Microsoft.Extensions.Configuration.FileExtensions包的引用。

要解决AddJsonFile，请添加对Microsoft.Extensions.Configuration.Json程序包的引用。

我正在使用Visual Studio 2017 v15.5开发一个.NET Core 2控制台应用程序。正如其他人指出的那样，在添加Microsoft.Extensions.Configuration之后，我需要添加Microsoft.Extensions.Configuration.Json来使AddJsonFile()调用工作。这也使SetBasePath()通话有效。所以我不需要添加Configuration.FileExtensions。（我的代码在有和没有它的情况下都可以编译并运行。）

我还打了一个电话AddEnvironmentVariables()，为此我需要添加Configuration.EnvironmentVariables。我的代码如下：

  var builder = new ConfigurationBuilder()
                    .SetBasePath(Directory.GetCurrentDirectory()) // requires Microsoft.Extensions.Configuration.Json
                    .AddJsonFile("appsettings.json") // requires Microsoft.Extensions.Configuration.Json
                    .AddEnvironmentVariables(); // requires Microsoft.Extensions.Configuration.EnvironmentVariables
  Configuration = builder.Build();

有趣的是，using我唯一需要的陈述是using Microsoft.Extensions.Configuration。

同时使用“ Microsoft.Extensions.Configuration”和“ Microsoft.Extensions.Configuration.Json”，这将解决问题。

https://www.nuget.org/packages/Microsoft.Extensions.Configuration/ https://www.nuget.org/packages/Microsoft.Extensions.Configuration.Json/

这是示例“ ConnectionFactory”

using System.Data;
using System.Data.SqlClient;
using Microsoft.Extensions.Configuration;
using System.IO;

namespace DataAccess.Infrastructure
{
 public class ConnectionFactory : IConnectionFactory
 {
    public ConnectionFactory()
    {
        var builder = new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory()).AddJsonFile("appsettings.json");
        Configuration = builder.Build();
    }


    public IConfigurationRoot Configuration { get; }
    public IDbConnection GetConnection
    {
        get
        {
            var connectionString = Configuration.GetConnectionString("DefaultConnection");
            var conn = new SqlConnection(connectionString);
            conn.Open();
            return conn;
        }
    }

    #region IDisposable Support
    private bool disposedValue = false; // To detect redundant calls

    protected virtual void Dispose(bool disposing)
    {
        if (!disposedValue)
        {
            if (disposing)
            {
                // TODO: dispose managed state (managed objects).
            }


            // TODO: free unmanaged resources (unmanaged objects) and override a finalizer below.
            // TODO: set large fields to null.

            disposedValue = true;
        }
    }

    // TODO: override a finalizer only if Dispose(bool disposing) above has code to free unmanaged resources.
    // ~ConnectionFactory() {
    //   // Do not change this code. Put cleanup code in Dispose(bool disposing) above.
    //   Dispose(false);
    // }

    // This code added to correctly implement the disposable pattern.
    public void Dispose()
    {
        // Do not change this code. Put cleanup code in Dispose(bool disposing) above.
        Dispose(true);
        // TODO: uncomment the following line if the finalizer is overridden above.
        // GC.SuppressFinalize(this);
    }
    #endregion
} }