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You can try catching the WM_SYSCOMMAND and checking if (WPARAM &amp;&nbsp;SC_CLOSE) == SC_CLOSE. If it is, then don't call the base class. <br />

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You can try catching the WM_SYSCOMMAND and checking if (WPARAM & SC_CLOSE) == SC_CLOSE. If it is, then don't call the base class.


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How can I disable the Close (&quot;x&quot;) button of the MDI child window ?<br />
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I tried to add the following code in the OnCreate virtual function of my child frame class:<br />
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CMenu * psysmenu = GetSystemMenu( FALSE );<br />
psysmenu-&gt;EnableMenuItem( SC_CLOSE, MF_DISABLED | MF_BYCOMMAND | MF_GRAYED );<br />
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It worked as long as the child window is not maximized, but if the child window is maximized then the &quot;x&quot; button is not disabled.
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How can I disable the Close ("x") button of the MDI child window ?

I tried to add the following code in the OnCreate virtual function of my child frame class:

CMenu * psysmenu = GetSystemMenu( FALSE );
psysmenu->EnableMenuItem( SC_CLOSE, MF_DISABLED | MF_BYCOMMAND | MF_GRAYED );

It worked as long as the child window is not maximized, but if the child window is maximized then the "x" button is not disabled.

Disable the Close system menu for MDI child window

Kernel and system programming is the process of creating the software necessary for a computer or device to function and operate other programs. Some operating systems (such as Microsoft Windows) are proprietary, but others, such as the various Linux distributions, are open source.