如何通过IP原理设置VSS凭据

Question

我正在尝试建立VSSconnection，以使用客户端库从我们的TFS中获取一些数据。我的认证有问题。构造我的VSS凭证时，凭证为空。当我建立与图书馆的连接时，该应用会崩溃：

  

TF400813：用户[我的计算机的主机名'无权访问此资源。

代码：

private IPrincipal _user;


    public VssConnection GetClient(Uri uri)
    {
        WindowsIdentity id = (WindowsIdentity) _user.Identity; 
        WindowsImpersonationContext impersonationContext;
        impersonationContext = id.Impersonate();
        WindowsIdentity newid = WindowsIdentity.GetCurrent();
        string name = newid.Name;
       //above gets my user name but below does not, and I don't know how to set it. 

        var credentials = new VssCredentials();
        return new VssConnection(uri,credentials);
    }


    public List<TeamProjectCollectionReference> GetCollectionNodes(List<string> selectedCollectionsList = null)
    {
        var client = GetClient(TfsUri);
       /*crashes here*/ var collectionClient = client.GetClient<ProjectCollectionHttpClient>();
        IEnumerable<TeamProjectCollectionReference> collectionNodes = collectionClient.GetProjectCollections().Result;

....