|
Thank you gentelman, good answer!
modified on Saturday, October 4, 2008 1:26 AM
|
|
|
|
|
Hi all,
i want to use CArchive for serilization data and have written a small class like the following one. The class contains two CArchive members. In one i want store data from the other i want load data.
I want to use a cast operator using the new class without overloading any >> and << operator from CArchive when serialize in and out data.
class TestArchive
{
public:
TestArchive():
oStore(new CMemFile(), CArchive::store)
oLoad(new CMemFile(), CArchive::load)
{;}
void SetLoadMode(bool bMode) {m_bLoadMode = bMode; }
operator CArchive&() { return m_bLoadMode ? oLoad : oStore; }
protected :
bool m_bLoadMode;
CArchive oStore;
CArchive oLoad;
...
};
...
using the class like that, (implicit casting)
CTestArchive oTestArchive;
Byte by = 255;
oTestArchive << by;
I got an error C2593 operator << is ambiguous.
With explicit casting CTestArchive to CArchive, it works fine.
(CArchive&)oTestArchive << by;
It seems to me, that the written cast operator is not used.
Any ideas ?
Regards
Wolfgang
modified on Friday, October 3, 2008 7:30 AM
|
|
|
|
|
I reckon you need to implement the << and >> operators in your class,redirecting the implementation to the correct member in each. There's no way the compiler is going to call your cast because it's to an unrelated type (not base class). The compiler can't know that the shift operators you intend to use are from the CArchive class unless you somehow tell it. I'm impressed that even the explicit cast version works it probably won't with older compilers.
"The secret of happiness is freedom, and the secret of freedom, courage."
Thucydides (B.C. 460-400)
|
|
|
|
|
Well, the explicit cast is a very rude tool, for instance
class A
{
public:
void foo(){ printf("foo\n");}
};
void main()
{
int i;
((A &)i).foo();
}
happily compiles.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
|
|
|
|
|
Hi all im getting error as :C1010: unexpected end of file while looking for precompiled header directive.. whenever i try to compile program with CppSQLite headers.. I included the sqlite.lib reference in thye linker options.. pls its urgent... i need to submit a mini project.. its dependent on ur help....
|
|
|
|
|
gkns wrote: pls its urgent
Well, you know, Google is very fast [^].
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
|
|
|
|
|
and if the previous answer doesnt help, read the comments (on about Page 5) of the CPPSqlLite article by Rob Groves, where someone had that exact issue and was given two ways of fixing it (one of which CPallini's google search found for you)
Often it helps to read through the comments at the bottom of an article ..
'g'
|
|
|
|
|
HI
im using HRGN stuff, i have 2 boxes that have a variable width and height, on mouse down in the corner ive coded it to change the width and the height variables and update but the two HRGN's dont update,
int nWidth = 550;
int nHeight = 400;
HRGN hRegion1 = CreateRectRgn(0, 0, nWidth, nHeight);
HRGN hRegion2 = CreateRectRgn(0, 0, nWidth, nHeight);
void ClientResize(HWND hWnd, int nWidth, int nHeight)
{
RECT rcWnd;
POINT pnt, pntDiff;
GetCursorPos(&pnt);
GetWindowRect(hWnd, &rcWnd);
if((pnt.x >= (rcWnd.right-20))&&(pnt.y >= (rcWnd.bottom - 20)))
{
pntDiff.x = pnt.x - nWidth;
nWidth += (int)pntDiff.x;
pntDiff.y = pnt.y - nHeight;
nHeight += (int)pntDiff.y;
MoveWindow(hWnd, rcWnd.left, rcWnd.top, nWidth, nHeight, TRUE);
}
}
LRESULT CALLBACK WndProc(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam)
{
case WM_CREATE:
g_Hwnd = hWnd;
dwStyle &= ~(WS_CAPTION|WS_SIZEBOX);
SetWindowLong(hWnd, GWL_STYLE, dwStyle);
CombineRgn(hRegion1, hRegion1, hRegion2, RGN_OR);
SetWindowRgn(hWnd, hRegion1, true);
break;
case WM_LBUTTONDOWN:
ClientResize(hWnd, nWidth, nHeight);
break;
case WM_LBUTTONUP:
UpdateWindow(hWnd);
break;
}
|
|
|
|
|
Sarriss wrote: but the two HRGN's dont update
I don't see any code that changes the regions there
Mark
Mark Salsbery
Microsoft MVP - Visual C++
![Java | [Coffee]](https://www.codeproject.com/script/Forums/Images/coffee.gif)
|
|
|
|
|
it changes the values used in the region, do i have to restate those regions then or is there a way of updating them
|
|
|
|
|
The values used to create the region have no relevance later.
Yes, you need to alter the regions if you want them altered.
Mark Salsbery
Microsoft MVP - Visual C++
|
|
|
|
|
Also note that once you call SetWindowRgn(), the window owns the region
(you aren't supposed to touch it).
You need to create a new region to update the window region again.
Mark
Mark Salsbery
Microsoft MVP - Visual C++
|
|
|
|
|
|
I want to know if any application is listening to my keyboard activity by set using the low level keyboard hook.
How can i do it ?
|
|
|
|
|
Pray for divine guidance. I am serious - that is about the only fool-proof way. Any way you can come up with to detect a hook, some malicious soul can defeat. At his worst, HWMNBN (he who must not be named) will install a keyboard filter and then you are totally at his monitoring-mercy.
How can you tell what is an "appropriate" use of a keyboard hook and what is a malicious one? Ain't no way.
Judy
|
|
|
|
|
Hi All
I have a problem to cut the string.How can i cut this string last file name. Old String
C:\abc\cd\as.txt And i want to show New String
C:\abc\cd
Plz help me
|
|
|
|
|
You can use of CStringMid or CString:Left.
|
|
|
|
|
You can use CString::ReverseFind() to get the zero based index of the last backslash and then truncate it with CString::Mid().
You can also use _splitpath() to split a path into its contents and then rebuild the string.
"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown
|
|
|
|
|
Can you give me example.Plz help me
|
|
|
|
|
Something like the snippet below
This is at the top of my head and I haven't tried to compile it, but you should get the idea anyway...
CString FullPath = _T("C:\\abc\\cd\\as.txt");
CString DirPath;
int nPos = FullPath.ReverseFind( _T('\\') );
if( nPos >= 0 )
{
DirPath = FullPath.Mid( 0, nPos + 1 );
}
"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown
|
|
|
|
|
How is declared your string?
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
|
|
|
|
|
This type
CString array[10]
|
|
|
|
|
Hence follow the Roger Stoltz's advice [^].
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
|
|
|
|
|
Sir My Problem is that i want to cut File name in the exiting string.
|
|
|
|
|
u can use the ReverseFind() and mid() functions to cut the file name. please check the examples the functions.
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
