从txt文件加载URL并在浏览器同步WebClient httpRequest中加载URL [英] Load URL from txt File and load the URL in Browser Synchronous WebClient httpRequest
问题描述
我从Microsoft的以下示例开始Windows Phone编程：
http://code.msdn.microsoft.com/wpapps/Hybrid-Web-App-75b7ef74/view/SourceCode
I started Windows Phone programming with this example from Microsoft: http://code.msdn.microsoft.com/wpapps/Hybrid-Web-App-75b7ef74/view/SourceCode
The应用仅显示浏览器并加载URL。
The app only displays the browser and load a URL.
现在，我想直接从.txt文件加载另一个URL。
例如： http://www.test.de/appurl.txt 和然后我要在Windows Phone应用中加载URL。
->例如： http://anotherserver.de/index.html?mobileApp
Now I want to load an other URL directly from a .txt file. For example: http://www.test.de/appurl.txt and then I want to load the URL in the Windows Phone App. --> For example: http://anotherserver.de/index.html?mobileApp
我的问题是URL必须同步加载而不是异步加载。我实现了AutoResetEvent，但是它不起作用...
My problem is, that the URL have to load synchronous and not asynchronous. I implement a AutoResetEvent, but it don´t work...
希望有人可以帮助我，谢谢！
Hope somebody can help me, thx!
这是我的代码：
public partial class MainPage : PhoneApplicationPage
{
// URL zur WebApp
// TODO: URL muss aus diesem TEXT-File ausgelesen werden!
private string _appURL = "http://www.test.de/appurl.txt";
public string _homeURL = "";
//private string _homeURL = "http://anotherserver.de/index.html?mobileApp";
// URL zur Registrierung von Angeboten
private string _registrationURL = "http://anotherserver.de/index.html?bereich=registrierung&mobileApp";
// Secondary tile data
//private Uri _currentURL;
//private Uri _tileImageURL;
//private string _pageTitle = "Shop ";
// Serialize URL into IsoStorage on deactivation for Fast App Resume
private Uri _deactivatedURL;
private IsolatedStorageSettings _userSettings = IsolatedStorageSettings.ApplicationSettings;
// To indicate when we're navigating to a new page.
private ProgressIndicator _progressIndicator;
// Constructor
public MainPage()
{
InitializeComponent();
//Read the URL from a txt file and set the _homeURL
ReadFile(_appURL);
// Setup the progress indicator
_progressIndicator = new ProgressIndicator();
_progressIndicator.IsIndeterminate = true;
_progressIndicator.IsVisible = false;
SystemTray.SetProgressIndicator(this, _progressIndicator);
// Event handler for the hardware back key
BackKeyPress += MainPage_BackKeyPress;
// Fast app resume events
PhoneApplicationService.Current.Deactivated += Current_Deactivated;
PhoneApplicationService.Current.Closing += Current_Closing;
}
//AutoResetEvent are = new AutoResetEvent(false);
public void ReadFile(string address)
{
var webClient = new WebClient();
webClient.OpenReadAsync(new Uri(address));
webClient.OpenReadCompleted += new OpenReadCompletedEventHandler(webClient_OpenReadCompleted);
// lock the thread until web call is completed
//are.WaitOne();
//finally call the NotifyComplete method to end the background agent
//NotifyComplete();
}
void webClient_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
{
try
{
using (var reader = new StreamReader(e.Result))
{
string downloaded = reader.ReadToEnd();
Debug.WriteLine("downloaded= " + downloaded);
_homeURL = downloaded;
//work = false;
}
}
catch
{
Debug.WriteLine("Please check your data connection");
MessageBox.Show("Please check your data connection");
}
//signals locked thread that can now proceed
//are.Set();
}
#region App Navigation Events
protected override void OnNavigatedTo(NavigationEventArgs e)
{
base.OnNavigatedTo(e);
// Browser event handlers
Browser.Navigating += Browser_Navigating;
Browser.Navigated += Browser_Navigated;
Browser.NavigationFailed += Browser_NavigationFailed;
Browser.IsScriptEnabled = true;
// Try to get the URL stored for fast app resume.
try
{
_deactivatedURL = (Uri)(_userSettings["deactivatedURL"]);
}
catch (System.Collections.Generic.KeyNotFoundException keyNotFound)
{
Debug.WriteLine(keyNotFound.Message);
}
// Were we started from a pinned tile?
if (NavigationContext.QueryString.ContainsKey("StartURL"))
{
// Navigate to the pinned page.
Browser.Navigate(new Uri(NavigationContext.QueryString["StartURL"], UriKind.RelativeOrAbsolute));
}
else if ((_deactivatedURL != null) && (e.NavigationMode != NavigationMode.Reset))
{
// If there is a stored URL from our last
// session being deactivated, navigate there
if (Browser.Source != _deactivatedURL)
{
Browser.Navigate(_deactivatedURL);
}
}
else
{
// Not launched from a pinned tile...
// No stored URL from the last time the app was deactivated...
// So, just navigate to the home page
Browser.Navigate(new Uri(_homeURL, UriKind.RelativeOrAbsolute));
}
}
....
推荐答案
我的问题是，URL必须加载同步而不是异步
My problem is, that the URL have to load synchronous and not asynchronous
不，您无法同步执行操作，但是使用 async / await 您可以伪装它。
No you can't do it synchronously, but using async/await you can pretend it.
为此，您可以使用类似这样的方法（甚至可以将其编写为扩展方法）
For this, You can use a method something like this (you can even write it as an extension method)
await Navigate(webBrowser1, "http://stackoverflow.com");
DoSomethingAfterNavigationCompleted();
Task Navigate(WebBrowser wb,string url)
{
var tcs = new TaskCompletionSource<object>();
WebBrowserDocumentCompletedEventHandler documentCompleted = null;
documentCompleted = (o, s) =>
{
wb.DocumentCompleted -= documentCompleted;
tcs.TrySetResult(null);
};
wb.DocumentCompleted += documentCompleted;
wb.Navigate(url);
return tcs.Task;
}
这篇关于从txt文件加载URL并在浏览器同步WebClient httpRequest中加载URL的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
