//ID of the package to be looked up
string packageID = "EntityFramework";
//Connect to the official package repository
IPackageRepository repo = PackageRepositoryFactory.Default.CreateRepository("https://packages.nuget.org/api/v2");
//Initialize the package manager string path = <PATH_TO_WHERE_THE_PACKAGES_SHOULD_BE_INSTALLED>
PackageManager packageManager = new PackageManager(repo, path);
//Download and unzip the package
packageManager.InstallPackage(packageID, SemanticVersion.Parse("5.0.0"));

简介

我在一些项目中使用nuget v2。最近，我测试了nuget v3，因为有很多包抛出错误，指示使用nuget v3。因此，我尝试在一个示例项目中测试nuget v3。我不是专家，但下载是有效的。

项目类型

我找到了3种类型的NuGet项目。

• PackagesConfigNuGetProject
• FolderNuGetProject
• MSBuildNuGetProject

PackagesConfigNuGetProject:

表示一个NuGet项目，由packages.config表示。

注意:它将在包中下载您的包。配置(实际上，它将在packages.config中为您的包添加一个条目)。您的NuGet包不会在您的磁盘中，而只在package .config中。所以如果你想获取或使用dll，你需要使用FolderNuGetProject#

FolderNuGetProject:

这个类表示一个基于文件夹的NuGetProject，比如VisualStudio解决方案中的packages文件夹。

如果您希望将软件包安装在磁盘上，请使用这个类。#

MSBuildNuGetProject:

这个类表示一个基于。net项目的NuGetProject。这也包含一个FolderNuGetProject的实例

我不知道你想用什么项目类型。在这个例子中，我选择了FolderNuGetProject.

<标题> 代码范例

1-初始化源存储库

List<Lazy<INuGetResourceProvider>> providers = new List<Lazy<INuGetResourceProvider>>();
providers.AddRange(Repository.Provider.GetCoreV3());
PackageSource packageSource = new PackageSource("https://api.nuget.org/v3/index.json");
SourceRepository sourceRepository = new SourceRepository(packageSource, providers);
Logger logger = new Logger();

2-初始化Nuget包管理器

var rootPath = @"yourPathToNugetFolder";
var settings = Settings.LoadDefaultSettings(rootPath, null, new MachineWideSettings());
var packageSourceProvider = new PackageSourceProvider(settings);
var sourceRepositoryProvider = new SourceRepositoryProvider(packageSourceProvider, providers);
var project = new FolderNuGetProject(rootPath);
var packageManager = new NuGetPackageManager(sourceRepositoryProvider, settings, rootPath)
{
    PackagesFolderNuGetProject = project
};

3-搜索一个包(在这个例子中我选择:Newtonsoft.Json)

var searchResource = await sourceRepository.GetResourceAsync<PackageSearchResource>();
var supportedFramework = new[] { ".NETFramework,Version=v4.6" };
var searchFilter = new SearchFilter(true)
{
    SupportedFrameworks = supportedFramework,
    IncludeDelisted = false
};
var jsonNugetPackages = await searchResource
    .SearchAsync("Newtonsoft.Json", searchFilter, 0, 10, logger, CancellationToken.None);

4-安装Newtonsoft.Json

在项目中安装nuget包时要小心。它将冻结UI。你应该使用BackgroundWorker或类似的东西来完成这个过程。

var allowPrereleaseVersions = true;
var allowUnlisted = false;
INuGetProjectContext projectContext = new ProjectContext();
ResolutionContext resolutionContext = new ResolutionContext(
    DependencyBehavior.Lowest,
    allowPrereleaseVersions,
    allowUnlisted,
    VersionConstraints.None);
var jsonPackage = jsonNugetPackages.First();
var identity = new PackageIdentity(jsonPackage.Identity.Id, jsonPackage.Identity.Version);
await packageManager.InstallPackageAsync(
    project,
    identity,
    resolutionContext,
    projectContext,
    sourceRepository,
    new List<SourceRepository>(),
    CancellationToken.None);

5-工具类

public class MachineWideSettings : IMachineWideSettings
{
    private readonly Lazy<IEnumerable<Settings>> _settings;
    public MachineWideSettings()
    {
        var baseDirectory = NuGetEnvironment.GetFolderPath(NuGetFolderPath.MachineWideConfigDirectory);
        _settings = new Lazy<IEnumerable<Settings>>(
            () => global::NuGet.Configuration.Settings.LoadMachineWideSettings(baseDirectory));
    }
    public IEnumerable<Settings> Settings => _settings.Value;
}
public class Logger : ILogger
{
    private List<string> logs = new List<string>();
    public void LogDebug(string data)
    {
        logs.Add(data);
    }
    public void LogVerbose(string data)
    {
        logs.Add(data);
    }
    public void LogInformation(string data)
    {
        logs.Add(data);
    }
    public void LogMinimal(string data)
    {
        logs.Add(data);
    }
    public void LogWarning(string data)
    {
        logs.Add(data);
    }
    public void LogError(string data)
    {
        logs.Add(data);
    }
    public void LogInformationSummary(string data)
    {
        logs.Add(data);
    }
    public void LogErrorSummary(string data)
    {
        logs.Add(data);
    }
}
public class ProjectContext : INuGetProjectContext
{
    private List<string> logs = new List<string>();
    public List<string> GetLogs()
    {
        return logs;
    }
    public void Log(MessageLevel level, string message, params object[] args)
    {
        var formattedMessage = String.Format(message, args);
        logs.Add(formattedMessage);
        // Do your logging here...
    }
    public FileConflictAction ResolveFileConflict(string message)
    {
        logs.Add(message);
        return FileConflictAction.Ignore;
    }

    public PackageExtractionContext PackageExtractionContext
    {
        get;
        set;
    }
    public NuGet.ProjectManagement.ExecutionContext ExecutionContext
    {
        get;
    }
    public XDocument OriginalPackagesConfig
    {
        get; set;
    }
    public ISourceControlManagerProvider SourceControlManagerProvider
    {
        get;
        set;
    }
    public void ReportError(string message)
    {
        logs.Add(message);
    }
    public NuGetActionType ActionType
    {
        get; set;
    }
    public TelemetryServiceHelper TelemetryService
    {
        get; set;
    }
}

希望这对你有帮助!