Develop Reference

Open file directly from SharePoint path with CSOM

I have a SharePoint server and I want to open files directly from the Server with SharePoint CSOM.
User clicks button --> the file (Excel, Word, ...) opens at the client machine with the standard software.
Directly means, that if I change something to the file and click save, that the file is directly saved on the SharePoint server (or if I click e.g. 'Save as' in Excel the suggested path is 'https://sharpoint.url.com/folder').
Actually I have:
using Microsoft.SharePoint.Client;
var clientContext = new ClientContext("https://sharpoint.url.com");
string relativePath = "/folder/file.xls";
clientContext.Credentials = CredentialCache.DefaultCredentials;
var file = clientContext.Web.GetFileByServerRelativeUrl(relativePath);
clientContext.Load(file);
clientContext.ExecuteQuery();
What do I have to do now, if I want to open the file directly (no download)?

I assume you ask how to access the file's stream instead of downloading it to a local folder.
You can use the File.OpenBinaryDirect method to get access to its ETag and stream, eg :
using(var fileInfo=File.OpenBinaryDirect(clientContext,"/folder/file.xls"))
using(var reader=new StreamReader(fileInfo.Stream))
{
//Do whatever you want with the data
}
BTW you shouldn't use the old xls files. The format is deprecated for over 10 years. The current Excel format, xlsx, is a zipped package of XML files that's better supported by SharePoint itself, doesn't require Excel to generate or read.
For example, if you wanted to read cell values from an xlsx file, you could use the popular EPPlus library to read directly from the stream:
using(var fileInfo=File.OpenBinaryDirect(clientContext,"/folder/file.xlsx"))
using(var package=new ExcelPackage(fileInfo.Stream))
{
var sheet=package.Workbook.Worksheets[0];
var value=ws.Cells["A1"].Value;
//...
}
UPDATE
It seems the question isn't related to programming after all. All that's needed to save or open a SharePoint document is clicking on the document's link. What happens then depends on the Open Documents in Client Applications setting at the site and document library level.
This affects the headers the server sends to the browser when the user clicks on a document link. The browser may still refuse to open the registered application and display the Save dialog.
If that doesn't work, you should check why instead of writing code. It's probably a configuration error or a browser setting. Solving it is easier than creating workarounds, pushing them to all client machines. And then keeping track of all the patches, where they are deployed and deploying new ones.
Apart from that, the Office applications know about SharePoint and document libraries since 2003. They can browse them, display SharePoint properties for the document, show collaborators etc.
As I mentioned in the question comments, a lot of what people think as "SharePoint Developoment" is nothing more that configuration, administration and end user features.
MSDN docs don't help either - they actually cause harm by not covering SP administration or explaining the features and how they are used. You'll find that in Technet. For years, people created webparts in code to change how grids looked because MSDN didn't explain how eg the DataViewWebPart worked or how you could style a grid from the UI.
In general, the best place for such questions is http://sharepoint.stackexchange.com. For example, check “Open in the client application” Vs “Use the server default (Open in the client application)” inside the document library advance settings

We can create Map Network Drive for SharePoint library, and open the file from the network location. Check article below:
http://support.sherweb.com/Faqs/Show/how-to-connect-to-a-sharepoint-site-using-webdav-sharepoint-2013
Or we can download the file from SharePoint and open it using the code below:
Application.Workbooks.Open(#"C:\Test\YourWorkbook.xlsx");
Reference: https://msdn.microsoft.com/en-us/library/b3k79a5x.aspx

Microsoft Office Document shows Sharepoint URL instead of Local

Situation: OneDrive for Business syncs files from Sharepoint Site Document Library to local directory:
C:\Users\users\Sharepoint\Library\Test.pttx
However with PowerPoint InterOp the:
presentation.Path
Is:
https://company.sharepoint.com/Library/Shared%20Documents/
Which is the correct path for Sharepoint.
How can I access the local directory?
Update: I found a similar question on MSDN but no answer

According to this post, the synced folders can be looked up in this multi-string registry value:
HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Common
\Internet\LocalSyncClientDiskLocation
Given that your local path and SharePoint URL look like
C:\Users\User\SharePoint\Library - Documents\Folder\SubFolder\Document.pptx and
https://***.sharepoint.com/Library/Shared%20Documents/Folder/SubFolder/Document.pptx,
you could try extracting the local part Folder/SubFolder/Document.pptx from the URL, add it to the local folder paths retrieved from the registry value and check for file existence.

If I understand correctly you want a way in Powerpoint (VSTO) to get the local path of the Sync'd directory? A method in the Powerpoint Object Model like presentation.GetLocalPath()?
I dont know why (in the MSDN link in your question) the MSFT CSG engineer said that it was impossible.
Sorry for the mistake, after the further investigation, it is
impossble. For the Word Application, the file is stored on the
OneDrive, and the "Offline" is cache mode for OneDrive, it is
transparent to Word Application (Word Application only know it is a
document on OneDrive), so when you check the location of the opened
document, the location is "http:/d.docs.live.net/xxxx/xx.docx" rather
than "C:\XXX\XXX".
This article shows you how you can Change the location where you sync SharePoint libraries on your computer. Obviously there isn't a method in the Powerpoint Interop Library but its definitely possible.
1) My first thought was to see if the OneDrive for Business sync app wizard saves any registry key or anything like that (using ProcessMonitor) but it probably stores the local directory in the cloud.
2) My second thought is a bit outside the box, just put a text file in https://company.sharepoint.com/Library/Shared%20Documents/LocalDrivePath.txt, then create an Extension method called presentation.GetLocalPath() and use the WebClient class to download the string.
Pseudo code:
public string GetLocalPath(this Microsoft.Office.Interop.PowerPoint.Presentation presentation)
{
WebClient client = new WebClient();
string localPath = client.DownloadString(presentation.Path + "LocalDrivePath.txt");
//Some good old protective programming to quickly identify the problem if the file doesn't exist
if (!string.IsNullOrEmpty(localPath)) throw new Exception("Issue: LocalDrivePath.txt not found in " + presentation.Path + Environment.Newline + "Please add the file for this Office Documents' sync'd (offline) local folder to be identified.");
return localPath;
}
Call it like so:
presentation.GetLocalPath();

Opening up PDFs and other documents from Silverlight out of browser

I'm having a little problem figuring out the best way to open up a file that I have stored in a database. The file is being stored as a byte array in a nvarbinary field in the database. Currently when I want to open up a file I use an ASP.NET webpage that I pass a variable to and write the file stream to the page. This works fine when using the in browser version of the Silverlight application, but when out of browser I cannot invoke a browser window to open because I don't have access to dom.
How can I open the bytearray from Silvelright without invoking a browser window? I'm able to pass the bytearray and file type to the Silverlight app no problem. I just don't know how to display it once I have it there..
Thanks!

If you are targeting windows (with full trust enabled, and not mac), you can do this out-of-browser by first writing the file to disk (either in isolated storage or in My Documents), then using a WScript.Shell COM object to have the OS open the file.
After you have saved the byte stream to a file and have the file location, you can do:
using (dynamic shell = AutomationFactory.CreateObject("WScript.Shell"))
{
shell.Run(fileLocation); //works similar to start -> run -> filename
}
If you want to leverage your existing ASP page, you can pass its URL to shell.Run and the OS will use the user's default browser to open that page.
On a mac, the best you could do is save the file to their user directory, and have them manually navigate there with finder and double-click it.

is there a way to avoid the 'open save save as' dialog in ie9 by registering a mime type?

I'm trying to bypass the 'open, save, save-as' dialog in ie9 for word perfect documents. Ideally my client wants wordperfect to pop up when a user clicks a link to a wpd doc without prompting the user. Is this possible to do this by defining a mime type?
http://msdn.microsoft.com/en-us/library/ms775148(v=vs.85).aspx
the above page mentions something about these registry entries but it's not clear to me weather this would solve my issue.
HKEY_LOCAL_MACHINE
Software
Microsoft
Windows
CurrentVersion
InternetSettings
Secure Mime Handlers
HKEY_CURRENT_USER
Software
Microsoft
Windows
CurrentVersion
InternetSettings
Secure Mime Handlers
Thanks

Are you sending the file using a HTTP Content-Type header of application/wordperfect? This is the first thing IE would look for to determine how to open the file.
The link you mentioned says
In Windows XP SP2 and later, after downloading a file, Internet Explorer consults the registry to find out which ProgID and CLSID is associated with the MIME type of the file. The browser then finds the ProgID and CLSID associated with the file name extension. If these ProgIDs do not match, and the CLSIDs do not match, Internet Explorer prompts the user before executing the file, as a safety precaution.
That is if you use Content-Type application-wordperfect and your file ends with .wpd then this would suffice to open the file automatically given WordPerfect registered itself with appropriate ProgIDs and CLSID upon installation.
You may check in your client's registry whether appropriate entries exist, the Registry Locations in that link show where you would have to look for them.

C# and Lotus notes attachment icon

I am using C# and need to attach a lnk (shortcut/link) file and email it to a lotus notes account. The problem is the icon defaults to a generic image and does not show the folder with the arrow as seen in Windows Explorer. A txt file icon does display as expected. I would like to control the appearance of that icon after it has been received. Can this be done through C# or is the Notes server the problem?

I think you are asking how to control the appearance of the icon once it arrives in the recipient's mail.
I do remember (from when we were on Notes here at work) that the icon was specific to the sender as opposed to the recipient (i.e. if I send you a Word document and I have Word 97 installed and you have 2003 installed, you'll see the Word 97 doc icon). But this appeared to be a function of the fact that I, the sender, was using Notes as the sending client. However, I think you may not be able to do what you want to do as one would assume you are sending regular SMTP e-mail. Assuming you are sending e-mail through the Notes server's SMTP interface, I don't believe you'll be able to control how the link appears on the recipient's side.