Use local images in Webbrowser control

问题:

I'm using a Webbrowser Control in my Wp7 app, but I can't seem to put images that are in the App directory, in the webbrowser.

I've put some images in a folder in the same directory as the .cs and .xaml files. Now I try to put them in the webbrowser control, but I can't seem to get this to work.

<img src="images/photo.jpg"/>
<img src="/images/photo.jpg"/>

The two above obviously don't work, my guess is that it should be something like this:

<img src="/SilverlightApplication;component/photo.jpg"/>

"SilverlightApplication" and "component" should be replaced by something else, but I don't know what :(

回答1:

You will need to store your images in the Isolated Storage and then display the images from there. I have put together a sample that you can download from the following location :-

www.smartmobiledevice.co.uk/projects/webbrowserimagesample.zip

This is based on the MSDN article How to: Display Static Web Content Using the WebBrowser Control for Windows Phone.

回答2:

On Windows Phone 8, where some WinRT classes are available, one can get a filesystem path of your app's isolated storage. So the absolute URL to a file in IsoStorage would be:

string URL = "file://" +
    Windows.Storage.ApplicationData.Current.LocalFolder.Path +
    "\\folder\\filename.png";

The WebBrowser control takes such URLs in a NavigateToString()'d HTML alright. Or you can designate IsoStorage as base and use relative URLs throughout. isostore: URLs don't work, I've tried. Neither do ms-appx://local/.

For completeness' sake, you can very similarly get a filesystem path to your app's resources. That'd be Windows.ApplicationModel.Package.Current.InstalledLocation.Path.

回答3:

well you can used dynamic images by concatenate the above given Paul example application update the array dynamically,

string[] files = {
        "readme.htm", "desert.jpg", "sample.jpg"
    };

and before to write to isolated you can delete the existing one

       private void SaveFilesToIsoStore()
    {
        //These files must match what is included in the application package,
        //or BinaryStream.Dispose below will throw an exception.
        string[] files = {
        "readme.htm", "desert.jpg", "sample.jpg"
    };

        IsolatedStorageFile isoStore = IsolatedStorageFile.GetUserStoreForApplication();
        if(isoStore.FileExists(files[0]))
        {
            isoStore.DeleteFile(files[0]);
        }

            foreach (string f in files)
            {
                StreamResourceInfo sr = Application.GetResourceStream(new Uri(f, UriKind.Relative));
                using (BinaryReader br = new BinaryReader(sr.Stream))
                {
                    byte[] data = br.ReadBytes((int)sr.Stream.Length);
                    SaveToIsoStore(f, data);
                }
            }
        }


    private void SaveToIsoStore(string fileName, byte[] data)
    {
        string strBaseDir = string.Empty;
        string delimStr = "/";
        char[] delimiter = delimStr.ToCharArray();
        string[] dirsPath = fileName.Split(delimiter);

        //Get the IsoStore.
        IsolatedStorageFile isoStore = IsolatedStorageFile.GetUserStoreForApplication();

        //Re-create the directory structure.
        for (int i = 0; i < dirsPath.Length - 1; i++)
        {
            strBaseDir = System.IO.Path.Combine(strBaseDir, dirsPath[i]);
            isoStore.CreateDirectory(strBaseDir);
        }

        //Remove the existing file.
        if (isoStore.FileExists(fileName))
        {
            isoStore.DeleteFile(fileName);
        }

        //Write the file.
        using (BinaryWriter bw = new BinaryWriter(isoStore.CreateFile(fileName)))
        {
            bw.Write(data);
            bw.Close();
        }
    }

回答4:

This is a very old thread, but I've come up with a solution, as we've just today updated a WP7 app.

The secret is to convert the image to a base 64 representation first, so start with this code:

    private string GetBase64(string f)
    {
        string ret = "";

        {
            StreamResourceInfo sr = Application.GetResourceStream(new Uri(f, UriKind.Relative));
            using (BinaryReader br = new BinaryReader(sr.Stream))
            {
                byte[] data = br.ReadBytes((int)sr.Stream.Length);
                ret = System.Convert.ToBase64String(data);
            }
        }
        return ret;
    }

Now, where you want to inject an image into the code (mine are gifs) use this

StringBuilder sb = ... // a string builder holding your webpage
String b64 = GetBase64("assets/images/filename.gif");

sb.AppendFormat(@"<img src='data:image/gif;base64,{0}' /></div>", b64);