我是 WP7 应用程序开发的新手,在将参数传递给网站上的 API 时遇到问题。
据我了解,在 WP7 上打开页面时首先触发 onNavigatedTo(),但是当我尝试获取参数时,首先触发 webClient_DownloadStringCompleted()。
public partial class Ranks : PhoneApplicationPage
{
private WebClient webClient;
private string pageType;
private string pagePosition;
public Ranks()
{
InitializeComponent();
this.webClient = new WebClient();
string header_auth = "application/json";
this.webClient.DownloadStringCompleted += new DownloadStringCompletedEventHandler(webClient_DownloadStringCompleted);
this.webClient.Headers[HttpRequestHeader.Authorization] = header_auth;
Uri serviceUri = new Uri(@"http://www.example.com/api/API.php?type=" + pageType + "&position=" + pagePosition);
this.webClient.DownloadStringAsync(serviceUri);
}
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
string type, position;
if (NavigationContext.QueryString.TryGetValue("type", out type))
{
pageType = type;
}
if (NavigationContext.QueryString.TryGetValue("pos", out position))
{
pagePosition = position;
}
}
void webClient_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
{
string myJsonString = e.Result;
List<PlayerDetails> dataSource = new List<PlayerDetails>();
//load into memory stream
using (var ms = new MemoryStream(Encoding.Unicode.GetBytes(myJsonString)))
{
//parse into jsonser
var ser = new DataContractJsonSerializer(typeof(PlayerDetails[]));
PlayerDetails[] obj = (PlayerDetails[])ser.ReadObject(ms);
foreach (PlayerDetails plyr in obj)
{
dataSource.Add(plyr);
}
playerList.ItemsSource = dataSource;
}
}
每当构建 URI 字符串时,它都会缺少参数“pageType”和“pagePosition”
任何帮助将不胜感激!