asp.net-core - .Net 核心 Ping 类 - System.Net.Ping 或 System.Net.Utilities

Question

我正在尝试开发一项功能，以在 .Net Core 应用程序中对网络上的 PC 执行 ping 操作。

根据这个StackOverflow ，它说我需要使用 System.Net.Utilities NuGet .

我的项目.json

{
  "dependencies": {
    "Microsoft.NETCore.App": {
      "version": "1.1.0",
      "type": "platform"
    },
    "BundlerMinifier.Core": "2.2.306",
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.1.0-preview4-final",
    "Microsoft.AspNetCore.StaticFiles": "1.1.0",
    "Microsoft.Extensions.Configuration.EnvironmentVariables": "1.1.0",
    "Microsoft.Extensions.Configuration.Json": "1.1.0",
    "Microsoft.Extensions.Logging": "1.1.0",
    "Microsoft.Extensions.Logging.Console": "1.1.0",
    "Microsoft.Extensions.Logging.Debug": "1.1.0",
    "Microsoft.Extensions.Options.ConfigurationExtensions": "1.1.0",
    "Microsoft.AspNetCore.Diagnostics": "1.1.0",
    "Microsoft.AspNetCore.Razor.Tools": "1.1.0-preview4-final",
    "Microsoft.AspNetCore.Routing": "1.1.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.1.0",
    "Microsoft.AspNetCore.Server.Kestrel": "1.1.0",
    "Dapper": "1.50.2",
    "Microsoft.EntityFrameworkCore.Tools": "1.1.0-preview4-final",
    "Microsoft.EntityFrameworkCore.SqlServer": "1.1.0",
    "Microsoft.EntityFrameworkCore.SqlServer.Design": "1.1.0",
    "Microsoft.VisualStudio.Web.CodeGenerators.Mvc": "1.1.0-preview4-final",
    "Microsoft.VisualStudio.Web.CodeGeneration.Tools": "1.1.0-preview4-final",
    "Microsoft.AspNetCore.Session": "1.1.0",
    "AutoMapper": "5.2.0",
    "Microsoft.AspNetCore.Mvc": "1.1.1",
    "System.Net.Utilities": "4.0.0-beta-23516"  
  },

  "tools": {
    "Microsoft.AspNetCore.Razor.Tools": "1.1.0-preview4-final",
    "Microsoft.EntityFrameworkCore.Tools": "1.1.0-preview4-final",
    "BundlerMinifier.Core": "2.2.306",
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.1.0-preview4-final",
    "Microsoft.VisualStudio.Web.CodeGeneration.Tools": {
      "version": "1.1.0-preview4-final",
      "imports": [
        "portable-net45+win8+wp8+wpa81"
      ]
    }
  },

  "frameworks": {
    "netcoreapp1.1": {
      "imports": [
        "dotnet5.6",
        "portable-net45+win81"
      ]
    }
  }
}

它添加了库，我可以毫无错误地构建它。但是在运行时，我不断收到此错误:

FileNotFoundException: Could not load file or assembly 'System.Net.Utilities, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. The system cannot find the file specified.

Unknown location
ReflectionTypeLoadException: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.

System.Reflection.RuntimeModule.GetTypes(RuntimeModule module)

但是，如果我使用 System.Net.Ping NuGet ，相同的代码没有任何错误，我可以 ping 主机。

根据 VS2015 Intellisense，它建议添加不起作用的 System.Net.Utilities 包。

我很困惑，无法弄清楚为什么在使用 System.Net.Utilities 时会出现该错误。通常，如果它与 .Net Core 不兼容，我们会直接得到引用错误/编译失败。但这一次完全不同，我根本无法浏览任何页面。

如果以防万一，这是我的 Ping 代码...

public async Task<double> PingPC(string host, int echoNum)
        {            
            long totalTime = 0;
            int timeout = 120;
            Ping pingSender = new Ping();

            for (int i = 0; i < echoNum; i++)
            {
                var reply = await pingSender.SendPingAsync(host, timeout);
                if (reply.Status == IPStatus.Success)
                {
                    totalTime += reply.RoundtripTime;
                }
            }
            return totalTime / echoNum;
        }

你能指出我做错了什么吗？谢谢。

Answer 1

要使此版本的 System.Net.Utilities 使用 VS 2015，您必须在导入部分添加 dnxcore50:

"netcoreapp1.1": {
  "imports": [
    "dnxcore50",
    "dotnet5.6",
    "portable-net45+win81"
  ]
}

如果您决定使用 VS 2017，根据这篇文章:http://www.natemcmaster.com/blog/2017/01/19/project-json-to-csproj/#imports ，您必须编辑您的 csproj 并在 PropertyGroup 中添加此行:

<PackageTargetFallback>dnxcore50</PackageTargetFallback>

这里有一个 VS2017 的工作示例:https://github.com/trenoncourt/ping-netcore