In a Silverlight application I sometimes need to connect to the web site where the application is hosted. To avoid hard coding the web site in my Silverlight application I use code like this:
WebClient webClient = new WebClient();
Uri baseUri = new Uri(webClient.BaseAddress);
UriBuilder uriBuilder = new UriBuilder(baseUri.Scheme, baseUri.Host, baseUri.Port);
// Continue building the URL ...
It feels very clunky to create a WebClient instance just to get access to the URL of the XAP file. Are there any alternatives?
Application.Current.Host.Source retrieves the URI of the XAP.
I use,
Uri baseUri = new Uri(Application.Current.Host.Source, "/");
// Example results:
// http://www.example.com:42/
// or
// https://www.example.com/
No string parsing needed!
You can also use this method to create full Urls, for example,
Uri logoImageUri = new Uri(Application.Current.Host.Source, "/images/logo.jpg");
// Example result:
// http://www.example.com/images/logo.jpg
This will build the root url in ASP.NET. You would then need to pass in baseUrl via Silverlight's InitParams and add "ClientBin\silverlight.xap".
// assemble the root web site path
var baseUrl = Request.Url.Scheme + "://" + Request.Url.Authority + Request.ApplicationPath.TrimEnd ('/') + '/';
In my case, I am not working in the main folder. I am working in h||p://localhost:1234/subfolder. That is no problem while working in Visual Studio IDE. But when moving to the server it fails. The following lines
Application.Current.Host.Source
can be replaced through a public function with result like this:
Public Sub AppPathWeb()
Res = Application.Current.Host.Source.AbsoluteUri.Substring(0, Application.Current.Host.Source.AbsoluteUri.LastIndexOf("/") + 1)
Return New Uri(Res)
End Sub
As Result, I can catch my files like this
MyImage = New Uri(AppPathWeb, "HelloWorld.jpg")
And the result is, that on server the url goes to h||p://mydomain.com/mysubfolder/HelloWorld.jpg"
Good luck
goldengel.ch
Related
I have to develop a webapp for a CEF-Browser environment. There is no HTTP server available, everything will be served over file:// protocol.
When developing a Webapp nowadays one doesn't get round working with a framework like react/vue for frontend. The standard webpack build scripts of those build a bundle which only works served over HTTP.
Is it possible to configure webpacks build bundle to work on file:// or is there another way to use react or vue via file://?
I'm suggest read CEF wiki more carefully. You are especially interested in https://bitbucket.org/chromiumembedded/cef/wiki/GeneralUsage.md#markdown-header-request-handling
In short:
You can register custom scheme handler to serve resources over http+custom fake domain.
You can pack resources in zip for example if you like, or leave them at file system as is (but in that case you can expect that some funny users can edit your files, and then report back unexisting errors back to you).
Important helpers already done (but you can write own when need.)
You can... many other things.
Main thing that "file" scheme are more restricted, and for example you can't do XHR requests. But for custom handler you can. Even if dynamic loader for some reason use XHR instead DOM-based loading it will work again same as on http without touching network.
cefclient itself also has usage of custom schemes. Check URL of Tests->Other... in menu. :)
PS: Sorry that my answer doesnt have direct answer for your question. But, custom resource handling in CEF is so common, that i'm just should say about.
fddima is right - you don't need to configure your webpack (although it would be theoretically possible). Instead you can use custom scheme handler in CEF. I made it work with angular at work.
I wrote blog post on how to serve web application via 'file' protocol in CEF.
What you want to add is your scheme handler and its factory:
using System;
using System.IO;
using CefSharp;
namespace MyProject.CustomProtocol
{
public class CustomProtocolSchemeHandler : ResourceHandler
{
// Specifies where you bundled app resides.
// Basically path to your index.html
private string frontendFolderPath;
public CustomProtocolSchemeHandler()
{
frontendFolderPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "./bundle/");
}
// Process request and craft response.
public override bool ProcessRequestAsync(IRequest request, ICallback callback)
{
var uri = new Uri(request.Url);
var fileName = uri.AbsolutePath;
var requestedFilePath = frontendFolderPath + fileName;
if (File.Exists(requestedFilePath))
{
byte[] bytes = File.ReadAllBytes(requestedFilePath);
Stream = new MemoryStream(bytes);
var fileExtension = Path.GetExtension(fileName);
MimeType = GetMimeType(fileExtension);
callback.Continue();
return true;
}
callback.Dispose();
return false;
}
}
public class CustomProtocolSchemeHandlerFactory : ISchemeHandlerFactory
{
public const string SchemeName = "customFileProtocol";
public IResourceHandler Create(IBrowser browser, IFrame frame, string schemeName, IRequest request)
{
return new CustomProtocolSchemeHandler();
}
}
}
And then register it before calling Cef.Initialize:
var settings = new CefSettings
{
BrowserSubprocessPath = GetCefExecutablePath()
};
settings.RegisterScheme(new CefCustomScheme
{
SchemeName = CustomProtocolSchemeHandlerFactory.SchemeName,
SchemeHandlerFactory = new CustomProtocolSchemeHandlerFactory()
});
I was wondering how I can achieve something like an HTTPClient.
I tried WebBrowser class but it seems that the execution continues even though the URL specified has not yet loaded.
public void testWebBrowser(){
final WebBrowser b = new WebBrowser(){
#Override
public void onLoad(String url) {
BrowserComponent c = (BrowserComponent)this.getInternal();
JavascriptContext ctx = new JavascriptContext(c);
// I want this Javascript context here
}
};
// just a test URL
b.setURL("http://youtube.com");
// Suppose to get the Javascript context here though it executes without waiting for the whole page to load
}
How can I get the JS Context from within a WebBrowser context? Like a synchronous execution
WebBrowser browser = new WebBrowser();
browser.setURL("someURL");
// wait execution till the whole page in "someURL" loads till it executes the next line
BrowserComponent c = (BrowserComponent)browser.getInternal();
JavascriptContext ctx = new JavascriptContext(c);
If I understand correctly you are trying to create a scraping solution?
That's probably not the ideal approach since this will actually create a web browser which you then need to automate with JavaScript. I would suggest you create a webservice that encapsulates the HttpClient functionality and drive it with ConnectionRequest. This way when the web site changes you can just fix your server in a way seamless to your installed base.
I have Silverlight application called MyApp. During startup MyApp loads MyApp.Main.xap module using the following code:
WebClient wc = new WebClient();
wc.OpenReadCompleted += new OpenReadCompletedEventHandler(onMainModuleLoaded);
Uri uri = new Uri("MyApp.Main.xap", UriKind.Relative);
wc.OpenReadAsync(uri);
It works. Within MyApp.Main I would like to load another xap file MyApp.Billing.xap, so I wrote like the same as above
WebClient wc = new WebClient();
wc.OpenReadCompleted += new OpenReadCompletedEventHandler(onBillingModuleLoaded);
Uri uri = new Uri("MyApp.Billing.xap", UriKind.Relative);
wc.OpenReadAsync(uri);
but it throws an error saying the file not found. MyApp.Billing.xap file is inside ClientBin folder and I can download it directly via absolute path in a browser. If I try to download MyApp.Billing.xap not from inside MyApp.Main, but from inside MyApp (instead of MyAPp.Main.xap) it also works fine. What might be the problem?
See if you have more success by using the various properties at Application.Current.Host.Source to put together a complete (absolute) uri, instead of trying to use a relative one (after all, what is it relative to?).
i'm developing an application and i would load an image that isn't in the clientbin folder, but in a folder placed in my server. I would do something like this
BitmapImage bit = new BitmapImage();
string path = "c:/image.png";
bit.UriSource = new Uri(path, UriKind.Absolute);
identity.Source = bit;
but it doesn't function.Any idea?
Thanks
Try:
Image.Source = New Imaging.BitmapImage(New Uri("http://www.Pic.jpg", UriKind.Absolute))
You do not want to include it in your project or the .xap will get huge.
Silverlight applications run on the client, not on the server, so referencing the path as you had been trying to do, would really point to the path on client machine running the application. However, Silverlight does not have rights to read or write from or to the client's disk anyway, due to sercurity reasons. The Isolated Storage functionality is the exception to that.
Therefore, your option is to try the first answer given by Bill, or a WebService, which is more complex to implement.
ib.
To add to Bill's answer. You can also use server side resources using the following helper method which is derived from the location of the xap file.
public static string GetUrlForResource(string resourcePage)
{
var webUrl = Application.Current.Host.Source.ToString();
//Get ClientBin Directory
var stub = webUrl.Substring(0, webUrl.LastIndexOf("/"));
//Get application root.
stub = stub.Substring(0, stub.LastIndexOf("/") + 1);
//Append the application root to the resource page.
webUrl = stub + resourcePage;
return webUrl;
}
To use it like Bill's answer, use the following:
Image.Source = new Imaging.BitmapImage(new Uri(GetUrlForResource("images/myimage.png"), UriKind.Absolute));
I'm tinkering with Silverlight 2.0.
I have some images, which I currently have a static URL for the image source.
Is there a way to dynamically load the image from a URL path for the site that is hosting the control?
Alternatively, a configuration setting, stored in a single place, that holds the base path for the URL, so that each image only holds the filename?
From what I gather you aren't trying to change the image itself dynamically, but rather to correctly determine the location of the image at runtime.
I believe simply prefixing the image relative URL with "../" should get you to the root of your application, not necessarily the site as the application might not be hosted in the root of a site.
If your XAP file is located as follows:
http://somesite.foo/app1/somethingelse/clientbin/MyFoo.xap
And you where trying to link the following image:
http://somesite.foo/app1/somethingelse/images/a/boo.png
Apparently all relative URI's are relative to where the XAP file is located (ClientBin folder typically) and Silverlight appends the current Silverlight client namespace. So if you Silverlight control is in the namespace Whoppa you would need to put all your images in the clientbin/Whoppa/ directory. Not exactly convenient.
The workaround is to use absolute URIs as follows:
new Uri(App.Current.Host.Source, "../images/a/boo.png");
In the code behind or a value converter you can do
Uri uri = new Uri("http://testsvr.com/hello.jpg");
YourImage.Source = new BitmapImage(uri);
// create a new image
Image image = new Image();
// better to keep this in a global config singleton
string hostName = Application.Current.Host.Source.Host;
if (Application.Current.Host.Source.Port != 80)
hostName += ":" + Application.Current.Host.Source.Port;
// set the image source
image.Source = new BitmapImage(new Uri("http://" + hostName + "/cute_kitten112.jpg", UriKind.Absolute));
http://www.silverlightexamples.net/post/How-to-Get-Files-From-Resources-in-Silverlight-20.aspx
using System.Windows.Resources; // StreamResourceInfo
using System.Windows.Media.Imaging; // BitmapImage
....
StreamResourceInfo sr = Application.GetResourceStream(new Uri("SilverlightApplication1;component/MyImage.png", UriKind.Relative));
BitmapImage bmp = new BitmapImage();
bmp.SetSource(sr.Stream);
SilverlightHost.Source will provide you the URL that was used to load the XAP file. You can use this to then construct a relative URL for your images.
So if for example your XAP is hosted on http://foo.bar/ClientBin/bas.xap and your images were stored in http://foo.bar/Images/ you can simply use the Source to grab the host name and protocol to construct the new URI.
img.Source = new BitmapImage(image uri) must work.
img.Source = new BitmapImage(new Uri("/images/my-image.jpg", UriKind.Relative)); will properly resolve to the root of the Silverlight application where as "../images/my-image.jpg" will not.
This is only true in the code-behind when dynamically setting the source of the image. You cannot use this notation (the "/" to designate the root) in the XAML (go fiquire, hope they fix that)
The below code worked for me only when the image is included in the project as a resource file:
img.Source = new BitmapImage(new Uri("/images/my-image.jpg", UriKind.Relative));
I am unable to access URL from absolute URLs. Not even Flickr's farm URL for images.