如何获取项目/解决方案任意深度的NuGet依赖树？

前置依赖 #

首先安装微软官方发布的NuGet相关NuGet包，这是NuGet.Core的官方替代实现，完全支持最新的项目格式和依赖规则：

• NuGet.ProjectModel：负责解析项目资产文件、构建依赖模型
• NuGet.Common：提供通用枚举、工具类支持
• NuGet.Protocol（可选）：如果需要从远程NuGet源直接拉取不在本地的包依赖树，可安装该包

核心实现逻辑 #

.NET 项目执行 dotnet restore 操作后，会在项目的obj目录下生成project.assets.json文件，该文件已经完整记录了当前项目全深度的所有依赖层级关系，不需要自行递归爬取NuGet源，解析效率极高。

代码示例 #

using NuGet.Common;
using NuGet.ProjectModel;
using System.Collections.Generic;
using System.IO;
using System.Linq;

public class NuGetDependencyTreeReader
{
    // 递归遍历依赖节点的辅助类
    public class DependencyNode
    {
        public string PackageName { get; set; }
        public string PackageVersion { get; set; }
        public List<DependencyNode> Dependencies { get; set; } = new();
    }

    public DependencyNode GetProjectDependencyTree(string projectAssetsFilePath)
    {
        // 读取assets文件
        var lockFile = LockFileUtilities.GetLockFile(projectAssetsFilePath, NullLogger.Instance);
        if (lockFile == null) return null;

        // 获取项目根节点信息
        var rootProject = lockFile.ProjectFileDependencyGroups.FirstOrDefault();
        var rootNode = new DependencyNode
        {
            PackageName = lockFile.PackageSpec.Name,
            PackageVersion = lockFile.PackageSpec.Version.ToString()
        };

        // 构建已加载包的缓存，避免循环依赖导致无限递归
        var loadedPackages = new Dictionary<string, DependencyNode>();
        var allLibraries = lockFile.Libraries.ToDictionary(lib => lib.Name, lib => lib);

        // 递归填充依赖
        foreach (var rootDependency in rootProject.Dependencies)
        {
            rootNode.Dependencies.Add(BuildDependencyNode(rootDependency.Name, rootDependency.VersionRange.OriginalString, allLibraries, loadedPackages));
        }

        return rootNode;
    }

    private DependencyNode BuildDependencyNode(string packageName, string version, IReadOnlyDictionary<string, LockFileLibrary> allLibraries, Dictionary<string, DependencyNode> loadedPackages)
    {
        var packageKey = $"{packageName}@{version}";
        if (loadedPackages.TryGetValue(packageKey, out var existingNode))
        {
            return existingNode;
        }

        if (!allLibraries.TryGetValue(packageName, out var library))
        {
            return new DependencyNode { PackageName = packageName, PackageVersion = version };
        }

        var node = new DependencyNode
        {
            PackageName = packageName,
            PackageVersion = library.Version.ToString()
        };
        loadedPackages.Add(packageKey, node);

        foreach (var dependency in library.Dependencies)
        {
            node.Dependencies.Add(BuildDependencyNode(dependency.Id, dependency.VersionRange.OriginalString, allLibraries, loadedPackages));
        }

        return node;
    }
}

解决方案级别适配 #

如果需要获取整个解决方案的依赖树，只需要遍历解决方案下所有项目的obj目录，读取每个项目的project.assets.json文件，将所有项目的根依赖节点合并即可。如果项目未生成资产文件，可先通过C#调用dotnet restore <解决方案路径>命令生成，不需要额外依赖。

内容的提问来源于stack exchange，提问作者Andrey Skvortsov