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Following my scenario.

I got an Application which loads a Filestructure (Folders, Files) from a Database into a WPF ListView. Now I'd like to grab a file from this ListView, drag it over my Desktop (or some open explorer window) and drop it there. Basic Drag and Drop, nothing fancy. This sounds like a "standard" function for a windows application - but google won't help.

So how can I achieve this? Interops?

Thanks

Edit: Thanks for the solution, I still had to do some googling. Here's my complete solution.

H.B.
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Dänu
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    it would be appreciated if you posted your complete solution as an answer here. – H H Sep 10 '11 at 15:12
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    I tried your example but it wont compile, DragDrop is unknown. Do I need to add a reference or something ? – GuidoG Nov 03 '15 at 10:52

1 Answers1

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DragDrop.DoDragDrop can do this as long as you pass it an appropriate DataObject.

First copy the files somewhere. You can use System.IO.Path.GetTempPath() if you don't have anywhere better.

Next create a string array containing the full paths to the files and do the following:

string[] paths = ...;
DragDrop.DoDragDrop(this, new DataObject(DataFormats.FileDrop, paths),
                    DragDropEffects.Copy);

It is actually possible to do this without pre-copying the files but that gets into some complicated IDataObject interactions, so unless your files are potentially very large and aren't already in the filesystem I would try this method first.

Gleno
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Ray Burns
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    I know this is a very old thread, but could you expand on your statement about "unless your files are potentially very large"-part? I'm trying to do exactly that. Have a DragDrop functionality, which downloads the file when dropping it somewhere. – Falgantil Apr 28 '15 at 07:11
  • How to do the same with DragAndDrop folders? – Argnist Sep 11 '15 at 03:48
  • @Argnist Same as files. Folder are treated as Files. – Aishwarya Shiva Sep 22 '15 at 19:49
  • @Ray-Burns Copying a large file to temp location might take a lot of time. Is there any other way to achieve this and resolve `IDataObject` interactions at the same time? Please have a look at my [Question Here](http://stackoverflow.com/questions/32725514/unable-to-drag-file-to-windows-explorer-from-a-wpf-listview) also. – Aishwarya Shiva Sep 22 '15 at 19:52
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    @AishwaryaShiva but they are not copied to explorer as files. I do DragDrop and nothing happens. – Argnist Sep 23 '15 at 11:05
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    @Ray-Burns where does the DragDrop object comes from ? I tried your example but DragDrop is not a know class. Do I need to add a reference ? – GuidoG Nov 03 '15 at 10:51
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    It should be noted that having the data in an array is crucial even if you have only one file! – TaW Jul 20 '17 at 08:18