Parse csv or excel file in Silverlight - silverlight

I've parsed these files in regular C# applications, but the IO methods for the files are different in Silverlight, and I can't seem to find the right methods. Searches haven't turned up any information I can use. For the real application I'll be receiving XML from the server, but for the prototype I just need to parse a file with some sample data in it.

You can save the Excel file as XML. An example can be found in this link
This way you can keep your import procedure the same and process the data as when you go live.

To access files from the user's machine you are required to use the OpenFileDialog and SaveFileDialog. Without elevated trust (requires out of browser apps) you will not be able to know anything more than the filename the user selected for input/saving; you will have no idea what the path is to this file. This function can only be called as the result of a user taking an action such as clicking a button; otherwise it will fail because Silverlight does not want malicious code prompting a user with annoying dialogs automatically.
To do this you would do something as follows:
var openFile = new OpenFileDialog();
if ( open.ShowDialog() == true ) // Sadly this is a nullable bool so this is necessary
{
using( Stream myStream = openFile.File.OpenRead() )
using ( var reader = new StreamReader( myStream ))
{
...
}
}

Related

Access Shared Preferences externally / Store a value into a new file and access it externally

I have the two following methods and I am using them to store a special value locally and be able to access it on application restart:
(Store value locally:)
private void SaveSet(string key, string value)
{
ISharedPreferences prefs = PreferenceManager.GetDefaultSharedPreferences(this);
ISharedPreferencesEditor prefEditor = prefs.Edit();
prefEditor.PutString(key, value);
// editor.Commit(); // applies changes synchronously on older APIs
prefEditor.Apply(); // applies changes asynchronously on newer APIs
}
(Read it again:)
private string RetrieveSet(string key)
{
ISharedPreferences prefs = PreferenceManager.GetDefaultSharedPreferences(this);
return prefs.GetString(key, null);
}
This works perfectly. Now is it possible to access and edit this Shared Preferences externally? Unfortunately, I cannot find any file when searching in folder
Phone\Android\data\com.<company_name>.<application_name>\files
nor anywhere else. I want / try to edit this value from my computer, after connecting the phone to it. Is this possible?
Alternatively: Can anyone maybe show me how to create a new file in the given path above, write/read it programmatically and how it stays there, even if application is closed / started again? So I can then edit this file with my computer anyhow?
I tried it with the following code, but unfortunately it doesn't work / no file is created or at least i cannot see it in the given path above:
//"This code snippet is one example of writing an integer to a UTF-8 text file to the internal storage directory of an application:"
public void SaveValueIntoNewFile(int value)
{
var backingFile = Path.Combine(System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal), "newFile.txt");
using (var writer = System.IO.File.CreateText(backingFile))
{
writer.WriteLine(value.ToString());
}
}
Would be very happy about every answer, thanks in advance and best regards
What you're looking for is where Android stores the Shared Preference file for applications that make use of it's default PreferenceManager.
I'd refer to this SO post which answers your question pretty well
SharedPreferences are stored in an xml file in the app data folder,
i.e.
/data/data/YOUR_PACKAGE_NAME/shared_prefs/YOUR_PREFS_NAME.xml
or the default preferences at:
/data/data/YOUR_PACKAGE_NAME/shared_prefs/YOUR_PACKAGE_NAME_preferences.xml
SharedPreferences added during runtime are not stored in the Eclipse
project.
Note: Accessing /data/data/ requires superuser
privileges
A simple method is to use Android Device Monotor,you can open it by clicking Tools--> android-->Android Device Monotor...
For example:
The path in my device is as follows:
/data/data/YOUR_PACKAGE_NAME/shared_prefs/YOUR_PACKAGE_NAME_preferences.xml
And we notice three buttons in the upper right corner of the picture.
The first one is used toPull a file from the device,the second one is used to Push a file onto the device,and the last one is used to delete the preferences.xml file.
So we can pull the preferences.xml file from current device to our computer and edit it as we want, and then push the updated preferences.xml to the folder again.Then we will get the value of preferences.xml file .

How to disable file in use check in WPF OpenFileDialog?

My WPF app is using the Microsoft.Win32.OpenFileDialog to select a SQL Server 2008 database to open.
It works OK but for one issue: When the database selected in the dialog was previously opened at some time since last boot, the file seems to be held open by SQL server in the background (even when it is not opened by my app and my app has been restarted). This causes a "file is used by another application" warning when OK is clicked in the OpenFileDialog and i can not use the dialog to open that particular database until the computer is rebooted. It seems the OpenFileDialog tries to open the file selected and doing that discovers that it is already opened by another app (SQL Server). How do i disable the OpenFileDialog from trying to open the selected file and just return the filename of the selected file without any checks?
My code looks like this:
public void OpenDatabase() {
// Let user select database to open from file browser dialog
// Configure open file dialog box
var dlg = new Microsoft.Win32.OpenFileDialog();
dlg.FileName = ""; // Default file name
dlg.DefaultExt = ".mdf"; // Default file extension
dlg.Filter = "Databases (.mdf)|*.mdf|All Files|*.*"; // Filter files by extension
dlg.CheckFileExists = false;
dlg.CheckPathExists = false;
// Show open file dialog box
bool? result = dlg.ShowDialog(); // Gives file in use warning second time!
// Process open file dialog box results
if (result == true) {
// Open document
string filename = dlg.FileName;
TryOpenDatabase(filename);
}
}
The underlying option is OFN_NOVALIDATE for early Windows versions, FOS_NOVALIDATE for the Vista dialog you get on later versions of Windows and .NET. The description from MSDN:
Do not check for situations that would prevent an application from opening the selected file, such as sharing violations or access denied errors.
Which is what you see happening now, the dialog sees a sharing violation on the database file. This option is in fact exposed on the OpenFileDialog wrapper class, add this line of code to fix your problem:
dlg.ValidateNames = false;
The MSDN forum has a post about this
It is in the OpenFileDialog API, you can turn that off using
ValidateNames = false
on the Dialog.

Download file with JSF

everyone!
I have a trouble. I tried to save excel file in jsf web application.
I generated file by my utils and trying to get "save" window, but I failed.
Here is my code:
<div>
<h:commandButton value="Apply" actionListener="#{hornPhonesBean.generateReport}"/>
</div>
and:
public void generateReport(ActionEvent event) {
System.out.println("GENERATE REPORT FROM = " + this.dateFrom + "; TO = " + this.dateTo);
try {
XSSFWorkbook workbook = (XSSFWorkbook) HornReportGenerator.getWorkbook(null, null);
String fileName = "1.xlsx";
FacesContext fc = FacesContext.getCurrentInstance();
ExternalContext ec = fc.getExternalContext();
// Some JSF component library or some Filter might have set some headers in the buffer beforehand. We want to get rid of them, else it may collide.
ec.responseReset();
// Check http://www.w3schools.com/media/media_mimeref.asp for all types. Use if necessary ExternalContext#getMimeType() for auto-detection based on filename.
ec.setResponseContentType("application/vnd.ms-excel");
// Set it with the file size. This header is optional. It will work if it's omitted, but the download progress will be unknown.
//ec.setResponseContentLength(contentLength);
// The Save As popup magic is done here. You can give it any file name you want, this only won't work in MSIE, it will use current request URL as file name instead.
ec.setResponseHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
OutputStream output = ec.getResponseOutputStream();
workbook.write(output);
output.flush();
output.close();
fc.responseComplete(); // Important! Otherwise JSF will attempt to render the response which obviously will fail since it's already written with a file and closed.
System.out.println("END");
} catch (Exception e) {
e.printStackTrace();
}
}
I read suggestions here and from another forums - everyone says I shouldnt use , but I didn't use it at all.
Then I thought that the problem could be in the
<ice:form>,
where I kept the
<h:commandButton>,
and I changed to
<h:form>,
but it didn't help.
Maybe the problem in the request - it has header Faces-Request partial/ajax. But I am not sure.
Please give me some ideas - I already spent 4 hours for this crazy jsf download issue)
Maybe the problem in the request - it has header Faces-Request partial/ajax. But I am not sure.
This suggests that the request is an ajax request. You can't download files by ajax. Ajax requests are processed by JavaScript which has for obvious security reasons no facilities to programmatically pop a Save As dialogue nor to access/manipulate client's disk file system.
Your code snippet does however not show that you're using ajax. Perhaps you oversimplified it too much or you're using ICEfaces which silently auto-enables ajax on all standard JSF command components.
In any case, you need to make sure that it's not sending an ajax request.
See also:
How to provide a file download from a JSF backing bean?
ICEfaces libary in classpath prevents Save As dialog from popping up on file download

Silverlight: Business Application Needs Access To Files To Print and Move

I have the following requirement for a business application:
(All of this could be on local or server)
Allow user to select folder location
Show contents of folder
Print selected items from folder (*.pdf)
Display which files have been printed
Potentially move printed files to new location (sub-folder of printed)
How can I make this happen in Silverlight?
Kind regards,
ribald
First of all, all but the last item can be done (the way you expect). Due to security protocols, silverlight cannot access the user's drive and manipulate it. The closest you can get is accessing silverlight's application storage which will be of no help to you whatsoever in this case. I will highlight how to do the first 4 items.
Allow user to select folder location & Show contents of folder
public void OnSelectPDF(object sender)
{
//create the open file dialog
OpenFileDialog ofg = new OpenFileDialog();
//filter to show only pdf files
ofg.Filter = "PDF Files|*.pdf";
ofg.ShowDialog();
byte[] _import_file = new byte[0];
//once a file is selected proceed
if (!object.ReferenceEquals(ofg.File, null))
{
try
{
fs = ofg.File.OpenRead();
_import_file = new byte[fs.Length];
fs.Read(_import_file, 0, (int)fs.Length);
}
catch (Exception ex)
{
}
finally
{
if (!object.ReferenceEquals(fs, null))
fs.Close();
}
//do stuff with file - such as upload the file to the server
};
}
If you noticed, in my example, once the file is retrieved, i suggest uploading it to a webserver or somewhere with temporary public access. I would recommend doing this via a web service. E.g
//configure the system file (customn class)
TSystemFile objFile = new TNetworkFile().Initialize();
//get the file description from the Open File Dialog (ofg)
objFile.Description = ofg.File.Extension.Contains(".") ? ofg.File.Extension : "." + ofg.File.Extension;
objFile.FileData = _import_file;
objFile.FileName = ofg.File.Name;
//upload the file
MasterService.ToolingInterface.UploadTemporaryFileAsync(objFile);
Once this file is uploaded, on the async result, most likely returning the temporary file name and upload location, I would foward the call to some javascript method in the browser for it to use the generic "download.aspx?fileName=givenFileName" technique to force a download on the users system which would take care of both saving to a new location and printing. Which is what your are seeking.
Example of the javascript technique (remember to include System.Windows.Browser):
public void OnInvokeDownload(string _destination)
{
//call the browser method/jquery method
//(I use constants to centralize the names of the respective browser methods)
try
{
HtmlWindow window = HtmlPage.Window;
//where BM_INVOKE_DOWNLOAD is something like "invokeDownload"
window.Invoke(Constants.TBrowserMethods.BM_INVOKE_DOWNLOAD, new object[] { _destination});
}
catch (Exception ex) { System.Diagnostics.Debug.WriteLine(ex.ToString()); }
}
Ensure you have the javascript method existing either in an included javaScript file or in the same hosting page as your silverlight app. E.g:
function invokeDownload(_destination) {
//some fancy jquery or just the traditional document.location change here
//open a popup window to http://www.myurl.com/downloads/download.aspx? fileName=_destination
}
The code for download.aspx is outside the scope of my answer, as it varies per need and would just lengthen this post (A LOT MORE). But from what I've given, it will "work" for what you're looking for, but maybe not in exactly the way you expected. However, remember that this is primarily due to silverlight restrictions. What this approach does is rather than forcing you to need a pluging to view pdf files in your app, it allows the user computer to play it's part by using the existing adobe pdf reader. In silverlight, most printing, at least to my knowledge is done my using what you call and "ImageVisual" which is a UIElement. To print a pdf directly from silverlight, you need to either be viewing that PDF in a silverlight control, or ask a web service to render the PDF as an image and then place that image in a control. Only then could you print directly. I presented this approach as a lot more clean and direct approach.
One note - with the temp directory, i would recommend doing a clean up by some timespan of the files on the server side everytime a file is being added. Saves you the work of running some task periodically to check the folder and remove old files. ;)

From Silverlight, generate file to save on user's computer without hitting server

I have a Silverlight app where I want to do an export of some data. The file output format is most likely going to be PDF or Word. But let's assume I can generate the file contents appropriately. I want to be able to pop up a Save dialog for the user to save this data or open it directly in the program.
Now obviously I could just launch the user to a URL and do the export on the server, and change the MIME type of the response to be either Word or PDF. This would work just fine. However, the sticking point is that I already have the correct data on the client (including complex filters and the like) and recreating this data set on the server just to send it back to the client again seems silly if I can avoid it.
Is there any way to take an existing set of data in Silverlight and generate a Word or PDF file and get it onto the user's computer? I could also do it from JavaScript using browser interop from Silverlight. I don't want to use out-of-browser Silverlight.
You need to use the SaveFileDialog class. Note that due to Silverlight's security settings, the SaveFileDialog needs to be opened as the result of a user event (e.g., a button click).
The dialog can be configured (if you want) using properties such as DefaultExt or Filter before you display it using the ShowDialog() method.
The ShowDialog() method will return true if the user correctly specified a file and clicked OK. If this is the case, you can then call the SaveFileDialog.OpenFile() method to access this file and write your data to it.
Example:
private void Button_Click(object sender, EventArgs e)
{
SaveFileDialog saveDialog = new SaveFileDialog();
if (saveDialog.ShowDialog())
{
System.IO.Stream fileStream = textDialog.OpenFile();
System.IO.StreamWriter sw = new System.IO.StreamWriter(fileStream);
sw.Write("TODO: Generate the data you want to put in your file");
sw.Flush();
sw.Close();
}
}

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