Can I reference local files in a webview when I use navigatetostring? - c#

I'm using a webview to display certain data in my windows 8 app. I would like to user an include to a local js file as well as use locally stored images.
Is this possible?
I haven't had any luck by putting the local path where the files are located.

According to WebView documentation you can only reference other files using the ms-appx-web protocol, i.e. to load the files stored in Windows.ApplicationModel.Package.Current.InstalledLocation, meaning that they need to be distributed as content along with your application. The control doesn't support ms-appdata protocol for security reasons, i.e. you can't open files stored Windows.Storage.ApplicationData.Current.LocalFolder Windows.Storage.ApplicationData.Current.RemoteFolder or Windows.Storage.ApplicationData.Current.TempFolder where you'd need to put them if you were generating or downloading them at runtime.
In JavaScript apps WebView is a bit more flexible: it does support ms-appdata protocol as well, but only for media files such as images. It cannot open any potentially executable code, such as script or CSS.

If you want to open some local .html file or atc. you should download it in InstalledLocation folder. If you haven't option to create a new file you can just use file.CopyAsync(htmlFolder, fname + ".html");
For example I create some .html file:
StorageFolder htmlFolder = await Windows.ApplicationModel.Package.Current.InstalledLocation.CreateFolderAsync(#"HtmlFiles", CreationCollisionOption.GenerateUniqueName);
IStorageFile file = await htmlFolder .CreateFileAsync(fname + ".html", CreationCollisionOption.GenerateUniqueName);
and than I can easily open this .html file with or without FileOpenPicker:
var fop = new FileOpenPicker();
fop.FileTypeFilter.Add(".html");
var file = await fop.PickSingleFileAsync();
if (file != null)
{
string myPath = file.Path.Substring(file.Path.IndexOf("HtmlFiles"));
myWebview.Navigate(new Uri("ms-appx-web:///" + myPath));
}
And don't forget - just only from InstalledLocation you can open it with ms-appx-web:///

If the WebView is IE10 based, FIleReader may be what you are looking for. Here is a snippet of code that I use on an image ipload page to show images in a page when they are selected via a File Open dialog:
$('input:file').each(function(index, evt){
if(index===0)
{
var files = evt.files;
for(var i=0;i<files.length;i++)
{
if(files[i].name===filename)
{
var reader = new FileReader();
reader.onload=(function(theFile){
return function(e){
var line= uploader.fineUploader('getItemByFileId',id);
if(line!=undefined)
$(line).append('<img class="fileimage" id="fileImage-' + id + '" src="'+e.target.result+'" />');
};
})(files[i]);
reader.readAsDataURL(files[i]);
break;
}
}
}
I hope this points you in the right direction!

Related

Upload Image to Dropbox with URL

DropboxClient dbx = new DropboxClient("my_Key");
var folder = "/Apps/Images";
var file = $"fileName.jpg";
var fileToUpload = #"C:\Users\LENOVO\Test\Test\test.jpg";
using (var mem = new MemoryStream(File.ReadAllBytes(fileToUpload)))
{
var updated = await dbx.Files.UploadAsync(folder + "/" + file,
WriteMode.Overwrite.Instance,
body: mem);
Console.WriteLine("Saved {0}/{1} rev {2}", folder, file, updated.Rev);
}
i want to upload Image to Dropbox. This code is worked but i want fileToUpload to be is a web URL because images is a Web Server. i know i can download every Images step by step. But this is a loss of performance. If i write a WebUrl in the fileToUpload. i see the exception. For Example:
fileToUpload = "https:\upload.wikimedia.org\wikipedia\commons\5\51\Small_Red_Rose.JPG"
The Exception:
C:\Users\LENOVO****\bin\Debug\net6.0\https:\upload.wikimedia.org\wikipedia\commons\5\51\Small_Red_Rose.JPG
*** - is a local folder name
i want to upload image to dropbox from Web
The UploadAsync method requires that you supply the data of the file to upload directly, as you are doing in your example by retrieving the file data from the local filesystem using File.ReadAllBytes.
If you want to upload a file to Dropbox directly from a URL without downloading it to your local filesystem first, you should instead use the SaveUrlAsync method.

UWP C# Windows IoT Read Text Line to Process Word [duplicate]

I am trying to read a text file named thedata.txt that has a list of words that I want to use in a hangman game. I have tried different ways, but I can't figure out where the file gets placed, if at all when the app runs. I added the file to my project, and I have tried setting the build properties to content, and then embedded resource, but can't find the file. I have made a Windows 10 universal app project. The code I tried looks like this:
Stream stream = this.GetType().GetTypeInfo().Assembly.GetManifestResourceStream("thedata.txt");
using (StreamReader inputStream = new StreamReader(stream))
{
while (inputStream.Peek() >= 0)
{
Debug.WriteLine("the line is ", inputStream.ReadLine());
}
}
I get exceptions.
I also tried to list the files in another directory:
string path = Windows.Storage.ApplicationData.Current.LocalFolder.Path;
Debug.WriteLine("The path is " + path);
IReadOnlyCollection<StorageFile> files = await Windows.Storage.ApplicationData.Current.LocalFolder.GetFilesAsync();
foreach (StorageFile file2 in files)
{
Debug.WriteLine("Name 2 is " + file2.Name + ", " + file2.DateCreated);
}
I don't see the file there either...I want to avoid hard coding the list of names in my program. I'm not sure what the path that the file is placed.
the code is very simple, you just have to use a valid scheme URI (ms-appx in your case) and transform your WinRT InputStream as a classic .NET stream :
var file = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///thedata.txt"));
using (var inputStream = await file.OpenReadAsync())
using (var classicStream = inputStream.AsStreamForRead())
using (var streamReader = new StreamReader(classicStream))
{
while (streamReader.Peek() >= 0)
{
Debug.WriteLine(string.Format("the line is {0}", streamReader.ReadLine()));
}
}
For the properties of the embedded file, "Build Action" must be set to "Content" and "Copy to Ouput Directory" should be set to "Do not Copy".
You can't use classic .NET IO methods in Windows Runtime apps, the proper way to read a text file in UWP is:
var file = await ApplicationData.Current.LocalFolder.GetFileAsync("data.txt");
var lines = await FileIO.ReadLinesAsync(file);
Also, you don't need a physical path of a folder - from msdn :
Don't rely on this property to access a folder, because a file system
path is not available for some folders. For example, in the following
cases, the folder may not have a file system path, or the file system
path may not be available. •The folder represents a container for a
group of files (for example, the return value from some overloads of
the GetFoldersAsync method) instead of an actual folder in the file
system. •The folder is backed by a URI. •The folder was picked by
using a file picker.
Please refer File access permissions for more details.
And Create, write, and read a file provides examples related with File IO for UWP apps on Windows 10.
You can retrieve a file directly from your app's local folder by using an app URI, like this:
using Windows.Storage;
StorageFile file = await StorageFile.GetFileFromApplicationUriAsync("ms-appdata:///local/file.txt");

Xamarin media plugin get android image path

I am using the media plugin for xamarin forms (by james montemagno) and the actual taking of the picture and storing it works fine, I have debugged the creation of the image on the emulator and it is stored in
/storage/emulated/0/Android/data/{APPNAME}.Android/files/Pictures/{DIRECTORYNAME}/{IMAGENAME}
however in my app it will get a list of file names from an API I want to check if the image exists in that folder.
The following works fine on IOS
var documentsDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
string jpgFilename = System.IO.Path.Combine(documentsDirectory, App.IMAGE_FOLDER_NAME);
jpgFilename = System.IO.Path.Combine(jpgFilename, name);
I have tried the 2 following methods for getting it on android but both are incorrect
var documentsDirectory = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
string jpgFilename = System.IO.Path.Combine(documentsDirectory, App.IMAGE_FOLDER_NAME);
jpgFilename = System.IO.Path.Combine(jpgFilename, name);
Java.IO.File dir = Android.OS.Environment.GetExternalStoragePublicDirectory(Android.OS.Environment.DataDirectory + "/" + App.IMAGE_FOLDER_NAME + "/" + name);
dir ends up as
/storage/emulated/0/data/{DIRECTORY}/{IMAGENAME}
jpgFileName ends up as /data/data/{APPNAME}.Android/files/{DIRECTORYNAME}/{IMAGENAME}
I dont want to hardcode anything in the paths but neither of these are right. I could not find anything in the GIT documentation for getting the file path except by looking at the path of the file created when taking a picture
The problem
I had the same kind of issue with Xamarin Media Plugin. For me, the problem is:
we don't really know where the plugin save the picture on android.
After reading all documentation I found, I just noted this:
... When your user takes a photo it will still store temporary data, but also if needed make a copy to the public gallery (based on platform). In the MediaFile you will now see a AlbumPath that you can query as well.
(from: Github plugin page)
so you can save your photo to your phone gallery (it will be public) but the path is known.
and we don't know what means "store the temporary data".
Solution
After investigating on how/where an app can store data, I found where the plugin stores photos on Android >> so I can generate back the full file names
In your Android app, the base path you are looking for is:
var basePath = Android.App.Application.Context.GetExternalFilesDir(null).AbsolutePath
It references your app's external private folder. It looks like that:
/storage/emulated/0/Android/data/com.mycompany.myapp/files
So finally to get your full file's path:
var fullPath = basePath + {DIRECTORYNAME} + {FILENAME};
I suggest you to make a dependency service, for instance 'ILocalFileService', that will expose this 'base path' property.
Please let me know if it works for you !
I resolved a similar problem. I wanted to collect all files for my app in a folder visible to all users.
var documentsDirectory = Android.OS.Environment.GetExternalStoragePublicDirectory(
Android.OS.Environment.DirectoryDocuments);
If you want to create Directory, add to your class using System.IO; and you have the same functions in a normal .NET application.
if (!Directory.Exists(path))
Directory.CreateDirectory(path);
If you want to create files or directory, you can use PCLStorage.
public async Task<bool> CreateFileAsync(string name, string context)
{
// get hold of the file system
IFolder folder = FileSystem.Current.LocalStorage;
// create a file, overwriting any existing file
IFile file = await folder.CreateFileAsync(name,
CreationCollisionOption.ReplaceExisting);
// populate the file with some text
await file.WriteAllTextAsync(context);
return true;
}
to get the private path
var privatePath = file.Path;
to get the public Album path
var publicAlbumPath = file.AlbumPath;
se the documentation here https://github.com/jamesmontemagno/MediaPlugin

c# UWP Save StorageFile Without Dialog

I am in trouble with some issue about FileSavePicker. Is there any solution about saving a StorageFile without showing any popup or dialog to ask user. I want to give the current path of the storage file from code behind.
var byteArray = Convert.FromBase64String(Base64);
StorageFile file = await Windows.Storage.ApplicationData.Current.LocalFolder.CreateFileAsync("file.jpg", CreationCollisionOption.ReplaceExisting);
await Windows.Storage.FileIO.WriteBytesAsync(file, byteArray);
var savePicker = new FileSavePicker();
savePicker.FileTypeChoices.Add("JPEG-Image", new List<string>() { ".jpg" });
savePicker.SuggestedSaveFile = file;
savePicker.PickSaveFileAsync();
...We have to use a few paths which are defined under
'Windows.Storage.KnownFolders'...
it is not so. In fact your app can access any folder on device but it will need additional permissions. The most straightforward way to obtain permission you should do next:
1) ask user to pick folder from FolderPicker
2) store selected folder to StorageApplicationPermissions.FutureAccessList
After this your app can do anything with this folder.
Code that demonstrate how to obtain permissions:
var picker = new FolderPicker();
var pfolder = await picker.PickSingleFolderAsync();
StorageApplicationPermissions.FutureAccessList.Add(pfolder);
Code that demonstrate how to create file in desired folder:
var folder = await StorageFolder.GetFolderFromPathAsync("your path");
var file = await folder.CreateFileAsync("text.txt");
using (var writer = await file.OpenStreamForWriteAsync())
{
await writer.WriteAsync(new byte[100], 0, 0);
}
But keep in mind that "your path" is folder or any of subfolder that was stored to StorageApplicationPermissions.FutureAccessList. More details here FutureAccessList
StorageFile.GetFileFromPathAsync() is probably what you are looking for. I think the file must be created beforehand for this method to work. Be aware that creating the file in some locations might need additional permissions or is even impossible (I don't know how UWP and UAC interact).
Another possibility is to use Win32 APIs inside UWP apps. Maybe this can solve your problem if the desired API is available.
I want to thank you all for your interest. I figured out the solution. If you do not want to use any dialog or prompting you can not use FileSavePicker. Here are the simple codes you need to converting Base64 string to image and save.
var byteArray = Convert.FromBase64String(Base64);
StorageFile file = await Windows.Storage.KnownFolders.SavedPictures.CreateFileAsync(
"file.jpg", CreationCollisionOption.ReplaceExisting);
await Windows.Storage.FileIO.WriteBytesAsync(file, byteArray);
I guess there is no way to give specific path. We have to use a few paths which are defined under Windows.Storage.KnownFolders. If it is not, please give some information about it.

Open downloaded epub files in WebView

I google a lot over this and still can't found a way to make it work
My app downloads epubs from many sources and then I save them to the local Storage (and unzip them)
I can read the extracted files with no problems with Storage commands but just can't to open it on WebView control
I tried all this:
The real path: C:\Data\Users\DefApps\APPDATA\Local\Packages\xxx\LocalState\***
Uri localUri = new Uri("ms-appx-web:///***/OEBPS/04_CL_CH.01.xhtml");
Uri localUri = new Uri("ms-appdata:///***/OEBPS/04_CL_CH.01.xhtml");
Uri localUri = new Uri("file:///***/OEBPS/04_CL_CH.01.xhtml");
Uri localUri = new Uri("file:///LocalState/***/OEBPS/04_CL_CH.01.xhtml");
Uri localUri = new Uri("file:///C://Data//Users//DefApps//APPDATA//Local//Packages//xxx//LocalState//***//OEBPS//04_CL_CH.01.xhtml");
// two ways
WebView1.Navigate(localUri);
WebView1.Source = localUri;
// this works, but as is an epub file, so need lot of files and styles
var XHTML = await Windows.Storage.ApplicationData.Current.LocalFolder.GetFileAsync("***\\OEBPS\\04_CL_CH.01.xhtml");
WebView1.NavigateToString(await Windows.Storage.FileIO.ReadTextAsync(XHTML));
This is a C# Windows Phone universal app, and I'm using VS 2013 Express
Take a look at http://blogs.windows.com/buildingapps/2013/07/17/whats-new-in-webview-in-windows-8-1/, it says:
ms-appdata:///local/TopLevelDirectory/file for files from the local
state
ms-appdata:///temp/TopLevelDirectory/file for files from the
app’s temporary state folder

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