ArgumentNullException未处理

Question

我是C＃和Windows Phone 7开发的新手，在尝试使用Dropnet API时遇到错误：

using DropNet;

namespace Hello
{

public partial class App : Application
{
    public PhoneApplicationFrame RootFrame { get; private set; }

    public static DropNetClient DropNetClient { get; set; }

    public App()
    {

        InitializeComponent();

        InitializePhoneApplication();

        DropNetClient = new DropNetClient("api key", "secret");
//I've correct app key and secret inserted here

        DropNetClient.GetTokenAsync((userLogin) =>
        {
            //Dont really need to do anything with userLogin, 
//DropNet takes care of it for now
        },
    (error) =>
    {
        //Handle error
    });

        var url = DropNetClient.BuildAuthorizeUrl();
//getting error here


    }
}

我得到的错误是

ArgumentNullException was unhandled
Value cannot be null
Parameter name: userLogin

根据http://dkdevelopment.net/what-im-doing/dropnet/，代码应该有效。请帮忙。

Answer 1

引自您提供的链接：

_client = new DropNetClient("API KEY", "API SECRET", "USER TOKEN", "USER SECRET");
// OR
_client = new DropNetClient("API KEY", "API SECRET");
_client.UserLogin = new UserLogin { Token = "USER TOKEN", Secret = "USER SECRET" };

您错过了UserLogin初始化。