Showing tag results for Code

Nov 24, 2003
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A shortcut to the Run dialog

Raymond Chen

Here's a little script that opens the Run dialog. You can save it as "Run.js" and double-click it. The advantage of this approach over various others people have come up with is that this one is actually documented. (And therefore is less likely to break in the next version of the operating system.)

CodeTips/Support
Nov 18, 2003
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Make sure the buttons match the question

Raymond Chen

When your program displays a dialog box with buttons, please make the buttons match the text. Consider this dialog, which appears after you install patches from Windows Update: It asks a yes/no question, but the options are "OK" and "Cancel". Either the buttons should be c...

Code
Nov 14, 2003
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Preventing edit control text from being autoselected in a dialog box

Raymond Chen

By default, when the user TABs to an edit control in a dialog box, the entire contents of the edit control are autoselected. This occurs because the edit control responds with the flag in response to the message. To prevent it from happening, remove that flag. All this subclass procedure does is remove the flag from the return value of the ...

Code
Nov 13, 2003
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Another different type of dialog procedure

Raymond Chen

The other method of using a window-procedure-like dialog box is to change the rules of the game. Normally, the window procedure for a dialog box is the function, which calls the dialog procedure and then takes action if the dialog procedure indicated that it desired the default action to take place. The dialog procedure is subservient to , prov...

Code
Nov 13, 2003
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Answer to previous exercise about m_fRecursing

Raymond Chen

Answer to previous exercise: The flag does not need to be per-instance. It only needs to be valid long enough that the recursive call that comes immediately afterwards can be detected. However, a global variable would not work because two threads might be inside the recursive call simultaneously. But a thread-local variable would work. (If you...

Code
Nov 12, 2003
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A different type of dialog procedure

Raymond Chen

In the discussion following my entry about dialog procedure return values, somebody suggested an alternate dialog design where you just call to do default actions (the same way you write window procedures and ) rather than returning TRUE/FALSE. So let's do that. In fact, we're going to do it twice. I'll cover one method today and cover an enti...

Code
Nov 11, 2003
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Safer subclassing

Raymond Chen

Answer to yesterday's homework assignment, with discussion.

Code
Nov 10, 2003
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Homework assignment about window subclassing

Raymond Chen

Window subclassing is trickier than you think. Consider this code sketch: What could go wrong? We'll discuss it tomorrow.

Code
Nov 7, 2003
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Returning values from a dialog procedure

Raymond Chen

For some reason, the way values are returned from a dialog procedure confuses people, so I'm going to try to explain it a different way. The trick with dialog box procedures is realizing that they actually need to return two pieces of information: Since tw...

Code
Nov 4, 2003
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Just follow the rules and nobody gets hurt

Raymond Chen

You may have been lazy and not bothered calling VirtualProtect(PAGE_EXECUTE) when you generated some code on the fly. You got away with it because the i386 processor page protections do not have a "read but don't execute" mode, so anything you could read you could also execute. Until ...

Code