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Accessing To A Struct With A Given Pointer
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Join Date: Apr 2005
Posts: 71
Reputation: 
Solved Threads: 1
Junior Poster in Training
We have a struct defined as :
Then we are sent a message...
And this is the code which gets the message
lParam contains the address of the struct. Here we want to access to the struct.
But there is a problem with the code. pWinPos is a constant pointer, so we can't simply assign an address to it.
So, finally, here is my question...
How can I access to the WINDOWPOS struct whose address is given by lParam
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typedef struct tagWINDOWPOS { /* wp */HWND hwnd;} WINDOWPOS;
HWND hwndInsertAfter;
int x;
int y;
int cx;
int cy;
UINT flags;
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WM_WINDOWPOSCHANGING
WPARAM wParamParameters
LPARAM lParam;
wParamThis parameter is not used.lParamPointer to a WINDOWPOS structure that contains information about the window's new size and position.
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case WM_WINDOWPOSCHANGING:WINDOWPOS * pWinPos;
pWinPos = lParam;
break;
But there is a problem with the code. pWinPos is a constant pointer, so we can't simply assign an address to it.
So, finally, here is my question...
How can I access to the WINDOWPOS struct whose address is given by lParam
pWinPos is not constant. but you do need a cast. either an old c style or a reinterpret_cast<WINDOWPOS*>(lParam)
Give your C++ a BOOST
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Join Date: Apr 2005
Posts: 71
Reputation:
Solved Threads: 1
Junior Poster in Training
Is convenient?
Then we can access to the sub-fields this way :
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WINDOWPOS wp;
WINDOWPOS * pwp;
pwp = ℘
Then we can access to the sub-fields this way :
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pwp->x
pwp->uflags
etc...
i prefer....
WINDOWPOS* wp = (WINDOWPOS*)lParam;
WINDOWPOS* wp = (WINDOWPOS*)lParam;
Give your C++ a BOOST
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