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winapimultiple-monitors

When can an HMONITOR be associated with multiple physical displays?

In one MSDN article, I read the following:

HMONITOR and the Device Context

Each physical display is represented by a monitor handle of type HMONITOR.

However, another article seems to contradict that statement:

GetPhysicalMonitorsFromHMONITOR function

A single HMONITOR handle can be associated with more than one physical monitor.

So my question is: under what circumstances will an HMONITOR be associated with multiple physical monitors?

Solution

  • An HMONITOR can be associated with multiple physical/virtual monitors like this:

    multi-monitors share a same HMONITOR

    When select 'Duplicate these displys' instead of 'Extend these displays', two physical/virtual monitors can share one HMONITOR, or in other word, they are totally overlapped. In this case, you may get two IDDCX_MONITORs(physical or virtual monitors) but only one HMONITOR.

    Actually, I'm finding way of mapping between IDDCX_MONITORs and HMONITORs:Map a IDDCX_MONITOR to a HMONITOR