I am writing a cross-platform application which generates PDF documents and then opens them with the standard PDF viewer. On Linux, updating (re-writing) an already opened document is no problem. The PDF viewer (have tried several) updates the displayed document after overwriting the file. I don't even have to trigger anything. This comes in very handy.
On Windows, however, I cannot overwrite a PDF document opened for reading by some viewer, because the viewers seem to open the document exclusively. Of course I cannot change the code of the viewers like Adobe Reader.
Is there any solution to this? I don't want to clutter the directory with arbitrary new file names, but rather use the same file name again. Deleting of the opened file is also forbidden on Windows.
I cannot determine which PDF viewer is used. In order to open the document, I use
cmd.exe /c start <fileName>
Related
I writing a code in vb.net. The codes will create a .rtf (wordpad file format). in that code i'm not only write text but a picture as well. the problem is windows always ask content security everytime i add a picture (fyi, picture already exist in my computer) into that file.
this is the preview
i tried to find setting in windows and wordpad, but still got nothing
how can i skip this security warning?
thank you
Just to clarify, I'm seeing the same issue. RTF created by hand by myself, new text with a few URLs, and pasted images captured by Windows screenshot grabbing app.
Dir /r was showing no alternate stream, but I still got the annoying message box every time I open the file.
Turns out the blocked content were the images, they also won't get copied to the clipboard. Tried grabbing them again, and pasting them to Paint and back to the document, and now WordPad likes them.
I have a power point file(.pptx) generated by a program that copies xml files and content files in a slide to other slides. It simply extracts xml files and content files from original power point file and then copies xml files, finally compresses the files as a zip file and renames the file to xxxxx.pptx. (The xml files I mentioned here is, of course, about Office Open XML)
When I open this file in Keynote on Mac OS X, it works well. No error happened.
However when I use PowerPoint application on Mac OS X, the app says "PowerPoint found a problem with content in xxxxx.pptx"
I think there are differences between PowerPoint specs and Keynote specs, so I need to apply the generated pptx file to the PowerPoint specs.
But, the error does not say WHERE or WHAT ERROR IS OCCURRED, but says there are some errors in that file.
So I cannot look for where is damaged in the generated file!
How do I detect the errors in the file or validate the format of it?
I do not want to get 'restore tools' but 'error detection tools'.
I simply used Open XML SDK 2.5 Productivity Tool.
In my situation, it said the Content-Type of xml files was different from expected one when I opened the pptx file. Soon, it occurred to me I forgot to change the data in [Content_Types].xml
After I fixed it, the file is opened without problems now!!
This app also shows codes in C# and validate each xml files individually.
Download Link is here ->
https://www.microsoft.com/en-us/download/details.aspx?id=30425
I want to create a a SpreadsheetML file on local drive which can be opened in MS Excel or Open Office by clicking on file in Windows Explorer.
I tried all filename extensions registered to Microsoft Excel i could find so far.
Some of them (.xls for example) allows file to be opened, but after "File is in different format than specified by the file extension" warning dialog. Some extensions (like .xlsx) causes Excel to show format error dialog without opening file.
Wikipedia tells that extension should be .xml, but it is registered to be opened by web browser by default.
This, this and this similar questions are about downloading a file from web and setting proper content-type. But i can not change content-type for local file.
This article explains how this annoying Extension Hardening mechanism works and how to disable it, but i think it is wrong to force user to disable security features just to allow spreadsheet file to be opened.
So there is no solution or am i missing something?
Now Open Office can open .xlsx (and read) files and Excel can open (and read) .ods files. My suggestion is to pick one of them that best suits your audience and your understanding of the specific file format.
Both of the applications have advantages and disadvanges and non-supported features between the two of them.
I suggest reviewing the document Differences between the OpenDocument Spreadsheet (.ods) format and the Excel (.xlsx) format.
When you work with two file formats, like .xlsx and .ods, there might
be formatting differences, and not all features will be available.
You’ll be able to convert data and content, but the way you work with
the content might be different depending on which formats you use.
One gotcha is with Open Office when you save a .xlsx file it will change the format to a .ods file. Both the applications will re-arrange the folder structure after saving anyway.
The biggest change is how you go about creating the SpreadsheetML files, both Open Office and Excel have a different folder structure depending on the file extension you will use.
Here is a short example of an Excel folder format.
-/
- _rels/
- .rels
- xl/
- _rels/
- workbook.xml.rels
- sheet1.xml
- workbook.xml
- [Content_Types].xml
I have created a sample GitHub repository for this with a sample that will open in both Excel and Open Office.
https://github.com/Nico-StackOverflow/proper-spreadsheetml-file-extension
I've implemented a user mode program and a Windows file system minifilter that creates a skeleton view of users files for a remote file storage system. It maps the remote files to the local drive. The user mode program creates a reparse tag for each file on the remote system. When a create request (e.g., CreateFile for read) is detected, the minifilter asks the user mode program to download the file. This should only happen when a program wants to open the file for viewing or editing.
But, I'm finding that Windows Explorer is triggering my files to download. I'd like to prevent the Explorer File windows and File Open/Save dialogs from
triggering downloads. And, I also want to display the file thumbnails and file
size.
[Update: I've found I can use Windows sparse files to show my remote
file size in Explorer. ]
Therefore, I have also implemented a Shell Extension, IThumbnailProvider, that downloads a rendition of the file. This provides the file thumbnails.
For my testing, I've registered the IThumbnailProvider for all files (*) and for .jpg files.
I'm seeing two interesting behaviors using a combination of Process Monitor and DebugView (both from SysInternals):
1. If I make my minifilter reject requests to open the file from Explorer, then my IThumbnailProvider is invoked.
2. If I permit open requests from Explorer, I see thumbcache.dll in the call stack trying to open the file and my IThumbnailProvider is not called. It appears that the default thumbnail provider reads the downloaded file and creates the thumbnail.
I must be missing something.
Update: if I use InitializeWithStream instead of InitializeWithFile, it appears my handler is invoked. But, that also triggers a download of the file.
There are many shell extension types which can access to your files. Icon handler can read file to create icon, Info tip handler can read file to create text hint, Data object handler can read file to create clipboard data and so on.
Questions from developer with the same problem: first and second. Solution was to create namespace shell extension. NSE can control all access to your files.
So, I wondered several times, what's the actual low-level difference when using "Cut" command in Windows, apart from Copy-Paste-Delete one, with focus being on the "Delete" part.
However, until now it wasn't really important, but I had some issues recently when using Cut-Paste in my application, when having an error in the process. The file that was being Cut-Pasted doesn't exist anymore, and can't be recovered by any data recovery software out there.
So I ran some tests, and it seems that it's true.
Anybody knows how the Cut-Paste commant works?
The clipboard
Windows manages an internal object called The Clipboard and provides an interface to put data in the clipboard, get the data from the clipboard, get meta information about the content of the clipboard (check if it is empty or there is any data there, get the type of the data a.s.o.). The operations with the clipboard (get, put) have copy semantics. They do not destroy the source data. The object currently kept in the clipboard can be get from there any time you want, it is not removed after the first "get" operation.
The clipboard can store a single object at any time. When an application puts something in the clipboard the previous content of the clipboard is lost. The clipboard can store the same data in multiple formats; is the application's responsibility to put it there in multiple formats, to query about the available formats and get the data in the format it wants. For example, an HTML-editor can put in the clipboard both the HTML source code of the selected text and the text as it is rendered in the browser (with different colors and fonts etc). Then, the same application or another application either gets the needed format depending on the context or provides a "Paste Special" command where it asks the user what format to use (see Microsoft Office programs or OpenOffice programs for example).
The clipboard is available (through the operations provided by Windows) to all the applications that want to use it and it is a powerful method to transfer data between applications. However, due to different formats used by different applications, it is not always possible to get data from an application and put it into another one. For example, a plain text editor like Notepad cannot Paste an image previously put in the clipboard by Paint, Photoshop or another graphic editor. This happens because Notepad just don't know how to handle anything but plain text.
The Cut, Copy and Paste semantic for applications that handle content (text, images etc)
It's up to each application how they use the clipboard. Implementing the Cut, Copy and Paste operations usually means:
Cut - the application puts (copies) to the clipboard the object selected in the document then remove it from the document;
Copy - the application puts (copies) to the clipboard the object selected in the document (but it does not remove it from the document);
Paste - the application gets (copies) from the clipboard the object stored there and puts into the current document; depending on the application, it is either inserted at the position of the caret, or replaces the current selection or it is simply inserted into the current container (folder or directory, in Windows Explorer); the content of the clipboard is not changed; a subsequent Paste is possible and it will do the same;
The Cut, Copy and Paste semantic for applications that handle files (Windows Explorer, for example)
Windows Explorer and other programs that works with files and not with pieces of text or image use a different semantic. The biggest difference from the model above is that Windows Explorer works with file names (with full paths) and not with the content of those files. It does not reads the file and it does not place the content of the file in the clipboard.
Cut - Windows Explorer copies the full path of the file into the clipboard; it also sets an internal flag that says "the file whose path is in the clipboard is meant to be moved by the next Paste"; it uses this flag to be able to render the cut file dimmed in all its windows until the operation completes or is aborted; it does not move or remove the file at this point;
Copy - Windows Explorer copies the full path of the file into the clipboard; it does not touch the file itself; then it clears the flag that was set on the last Cut operation; the file that was previously cut (if any) is now rendered again using the same style as the other files (no dim, no nothing); in other words, a Copy cancels any previous Cut;
Paste - Windows Explorer gets the file path from the clipboard; it copies the file pointed by that path into the current directory; what it does after that depends on its internal flag for Cut operation; if the flag is set then the file was cut before (see Cut and Copy above) then it will remove the file from their original location and also the flag; otherwise (when the Cut flag is not set because the last operation was a Copy), it does not affect the original file in any way.
Remarks on Windows Explorer's behaviour
It's important to notice that Windows Explorer does not put the file content in the clipboard. If you use the Cut or Copy command in Explorer then you delete the file, it will not be able to Paste it in a different directory because the file does not exist any more and it cannot copy an object that does not exist.
Also, a file that was Cut in Windows Explorer cannot be Pasted multiple times in different directories because Explorer pairs the Cut with the first Paste (if there was no Copy in the meantime) and produces a move operations from them. After the Paste the Cut flag is removed and, even if it is not removed, there is no way to move the file again because it is not on the path stored in clipboard any more.
I'm not on Windows now (I didn't use Windows in the last 3 years) but as far as I remember, you can Copy a file once then Paste it several times; a Copy followed by a Paste produces a copy of the file and as long as the source is still there, subsequent Paste operations can produce more copies.
Sure, an error that happens on the most inconvenient moment can produce data loss. Due to the way Windows Explorer handles the files and the errors that might happen, it is very unlikely that it accidentally removes a file during a Cut-Paste operation without putting it into the destination folder.
I'm absolutely confident that more files are lost due to human error than because of errors that happen during the execution of Windows Explorer.
Other applications
Other applications work in different ways. Most of those that deal with content (text, image, sound, video, etc) work as explained in the section about content. Most of those that deal with files work similar with Windows Explorer.
Another application can get the data that was put in the clipboard but Windows Explorer. It's up to that application to interpret it as plain text and put the file path it gets from clipboard into the current document as is (Notepad works this way) or recognize it is a file path and attempt to copy the file (or do something else with it). Another window or instance of Explorer does it, maybe other file managers do it too.
Multiple-clipboard applications
The programs from the Microsoft Office Suite (Word, Excel a.s.o) and also some other applications implement a multiple-clipboard feature. This functionality is not provided by Windows clipboard. These applications work with the clipboard as usual but the also keep a history of the objects they put into the clipboard in the past and offer the user a list of these objects for re-use. For compatibility and integration with other applications they also get from and put into the clipboard the object that the user selects for re-use. The Windows clipboard, however, still contains a single object, the last one that was put there by any application.