如何在.NET 6控制台应用程序中加载.NET 6项目

Question

我试图在.NET 6控制台应用程序中加载.NET 6项目(SDK样式)。我的整个项目相当简单--当它从默认的输出文件夹运行时，它实际上尝试加载自己的.csproj文件：

using Microsoft.Build.Evaluation;

namespace ProjLoading
{
    internal class Program
    {
        static void Main(string[] args)
        {
            var projectLocation = "../../../ProjLoading.csproj";
            var project = new Project(projectLocation, null, null, new ProjectCollection());
        }
    }
}

我使用以下nuget软件包：

• Microsoft.Build (17.2.0)
• Microsoft.Build.Utilities.Core (17.2.0)

当我运行代码时，我会得到以下异常：

Microsoft.Build.Exceptions.InvalidProjectFileException: 'The SDK 'Microsoft.NET.Sdk' specified could not be found.  C:\Users\vchel\source\repos\ProjLoading\ProjLoading\ProjLoading.csproj'

This exception was originally thrown at this call stack:
    Microsoft.Build.Shared.ProjectErrorUtilities.ThrowInvalidProject(string, Microsoft.Build.Shared.IElementLocation, string, object[])
    Microsoft.Build.Evaluation.Evaluator<P, I, M, D>.ExpandAndLoadImportsFromUnescapedImportExpressionConditioned(string, Microsoft.Build.Construction.ProjectImportElement, out System.Collections.Generic.List<Microsoft.Build.Construction.ProjectRootElement>, out Microsoft.Build.BackEnd.SdkResolution.SdkResult, bool)
    Microsoft.Build.Evaluation.Evaluator<P, I, M, D>.ExpandAndLoadImports(string, Microsoft.Build.Construction.ProjectImportElement, out Microsoft.Build.BackEnd.SdkResolution.SdkResult)
    Microsoft.Build.Evaluation.Evaluator<P, I, M, D>.EvaluateImportElement(string, Microsoft.Build.Construction.ProjectImportElement)
    Microsoft.Build.Evaluation.Evaluator<P, I, M, D>.PerformDepthFirstPass(Microsoft.Build.Construction.ProjectRootElement)
    Microsoft.Build.Evaluation.Evaluator<P, I, M, D>.Evaluate()
    Microsoft.Build.Evaluation.Project.ProjectImpl.Reevaluate(Microsoft.Build.BackEnd.Logging.ILoggingService, Microsoft.Build.Evaluation.ProjectLoadSettings, Microsoft.Build.Evaluation.Context.EvaluationContext)
    Microsoft.Build.Evaluation.Project.ProjectImpl.ReevaluateIfNecessary(Microsoft.Build.BackEnd.Logging.ILoggingService, Microsoft.Build.Evaluation.ProjectLoadSettings, Microsoft.Build.Evaluation.Context.EvaluationContext)
    Microsoft.Build.Evaluation.Project.ProjectImpl.Initialize(System.Collections.Generic.IDictionary<string, string>, string, string, Microsoft.Build.Evaluation.ProjectLoadSettings, Microsoft.Build.Evaluation.Context.EvaluationContext)
    Microsoft.Build.Evaluation.Project.Project(string, System.Collections.Generic.IDictionary<string, string>, string, string, Microsoft.Build.Evaluation.ProjectCollection, Microsoft.Build.Evaluation.ProjectLoadSettings, Microsoft.Build.Evaluation.Context.EvaluationContext, Microsoft.Build.FileSystem.IDirectoryCacheFactory)
    ...
    [Call Stack Truncated]

我正在从Visual 2022 (17.2.2)构建/运行这个控制台应用程序。

我该如何解决这个问题？

Answer 1

我不明白为什么，但我遇到了这个解决方案，它解决了这个问题：

https://blog.rsuter.com/missing-sdk-when-using-the-microsoft-build-package-in-net-core/

如果链接在将来失效，我的整个项目现在将环境变量MSBUILD_EXE_PATH设置为msbuild的最新版本，如下面的代码所示：

using Microsoft.Build.Evaluation;
using System.Diagnostics;
using System.Text.RegularExpressions;

namespace ProjLoading
{
    internal class Program
    {
        static void Main(string[] args)
        {
            var startInfo = new ProcessStartInfo("dotnet", "--list-sdks")
            {
                RedirectStandardOutput = true
            };

            var process = Process.Start(startInfo);
            process.WaitForExit(1000);

            var output = process.StandardOutput.ReadToEnd();
            var sdkPaths = Regex.Matches(output, "([0-9]+.[0-9]+.[0-9]+) \\[(.*)\\]")
                .OfType<Match>()
                .Select(m => System.IO.Path.Combine(m.Groups[2].Value, m.Groups[1].Value, "MSBuild.dll"));

            var sdkPath = sdkPaths.Last();
            Environment.SetEnvironmentVariable("MSBUILD_EXE_PATH", sdkPath);

            var projectLocation = "../../../ProjLoading.csproj";
            var project = new Project(projectLocation, null, null, new ProjectCollection());
        }
    }
}