Notes mostly originating from a bomb shell dropped by Mike, (SpeakEasy). The Windows Clipboard
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Nov 2022 https://www.eileenslounge.com/viewto...301028#p301028 3 Office Windows Clipboard
Nov 2022 https://www.eileenslounge.com/viewto...300947#p300947 1 Mike we only have 1 windows clipboard …… just the Windows clipboard. The Office clipboard is just a specific view ….. the clipboard is owned at any particular point in time by the window (or task) that last placed data in the clipboard. In conjunction with this, an application can request that data it is putting on the clipboard use something called 'deferred render' mode - this means that the data is not actually put on the clipboard at that time, the intended purpose being related to performance - it is only provided when a request to paste the data is made. Data marked for deferred render is removed from the clipboard when the owning window is closed. Excel seems to mark quite a lot of data for deferred rendering .
For a range Excel puts about 30 different formats of the data on the clipboard in the following orderexcelclipboarformats.jpg
The 'Office clipboard' and 'Excel clipboard' are just limited viewers of the Windows clipboard. As indicated above, the source application has the responsibility of putting all the formats it deems necessary onto the clipboard. The consuming app iterates that list of formats to see which ones it supports.
so what’s this then https://www.eileenslounge.com/viewto...300955#p300955 4
so any application can monitor (and display to the best of their ability) the contents of the clipboard*. (* this, by the way, is why you can find a plethora of applets that purport to show the contents of the clipboard such as FreeClipView and ClipDiary (back in the day - XP - Microsoft had their own proper clipboard viewer, but they got rid of it; I suspect because it used the slightly unstable clipboard viewer chain mentioned above; the replacement in Windows 10, which only works if you turn on clipboard history - yes they added a history capability to the OS - lacks features ...)) …. This used to be by inserting a clipboard viewer into the clipboard viewer chain - but this is not as robust as it might be, and is the source of some of the 'bugs' that you refer to (e,g. if applications fail to maintain the clipboard viewer chain properly or if a window in the clipboard viewer chain stops responding to messages). The current best practice method is to create a Clipboard Format Listener, which then receives notifications every time the clipboard changes. Applications are free to display the current contents of the clipboard that they understand in order to show the user what is available to paste. And that's what the Office clipboard is: simply a bespoke view of the Windows clipboard, not an actual separate clipboard. There IS a minor wrinkle to this - the Office clipboard viewer maintains a history of clipboard entries (the clipboard itself can only ever hold one entry). Again without going into the nitty gritty, this history consists of data formats that the Office applications know how to render. This can cause some minor inconsistencies..
something somewhere is telling the clipboard - Indeed. Specifically, the WM_RENDERFORMAT message - Sent to the clipboard owner if it has delayed rendering a specific clipboard format and if an application has requested data in that format. The clipboard owner must render data in the specified format and place it on the clipboard by calling the SetClipboardData function.
The .Copy method puts a copy of the object you are referencing onto the clipboard, in this case a Range.- and then synthesizes all the supported formats. including the Text format (which it does as the synthesized CF_TEXT format, which always ends CR LF [in fact it is even more clever than that, in that it actually separates Rows with CR LF and columns by Tab])
The DataObject's .SetText method exposed to VBA, on the other hand, expects a straightforward text string
(Oh, and one other thing: .PutInClipboard can perform ... unexpectedly ... on occasion if Windows file explorer is open.)
https://www.eileenslounge.com/viewto...301028#p301028 14
Nov 2022 https://www.eileenslounge.com/viewto...301028#p301028 6 the windows clipboard ….. there is no such thing as an Excel Clipboard, and not even anything that might be considered as similar. _____ This thing, Let Application.CutCopyMode = False , is often said to clear the Excel Clipboard.
How about: It takes it out of the (Windows) Clipboard. So if you do a .Paste nothing will happen, as the (Windows) Clipboard is now empty, and the stupid thing is not as clever as that “Office thing that is similar to a clipboard” (that thing what we might call, for want of a better name, the Office Clipboard) , so it wont remember what was copied before. I note that Let Application.CutCopyMode = False makes the clipboard symbol go from orange to white. So maybe that is an indication of if the (Windows) Clipboard is occupied or not._.____________________________
That “Office thing that is similar to a clipboard” (that thing what we might call, for want of a better name, the Office Clipboard) , seems to hold a copied range including the format, long after other things have been copied , even if Let Application.CutCopyMode = False was used a few times, and even if the workbook from which it was copied has long since been closed. In fact, close Excel, go into Word, take a peek into the Office thing that is similar to a clipboard” (that thing what we might call, for want of a better name, the Office Clipboard) there, and you can also pick that copied Excel range out, and paste that copied Excel range into word. But now things are getting a bit inconsistent and quirky: I am finding that sometimes it will give me the formats and sometimes not, - Oh dear, Microsoft got their clipboard viewer chain in a tangle I expect._.____________________
I have often regarded the .Paste as using the Windows Clipboard, whereas I regarded the Excel .PasteSpecial function as using the Excel Clipboard.
Maybe .Paste is using the (Windows) Clipboard whereas the Excel .PasteSpecial function is just some coding to help you choose which version of the copy in the (Windows) Clipboard that you use.
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