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The -1 is because it was incremented just prior to bailing out of the loop so that puts it back to where it should be.
For generating binary strings I usually use a bitmasking scheme. Something like this :
void GenBinaryString( BYTE byte, CString &str )
{
str = _T( "" );
const int bytebits = 8;
BYTE mask = 1 << ( bytebits - 1 );
for( int x = 0; x < bytebits; x++, mask >>= 1 )
{
str += ( mask & byte ) ? _T( "1" ) : _T( "0" );
if( x == 3 )
str += _T( " " );
}
}
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Thanks
but your coding look more complicating to me.. T_T
Can you explain this clearly with comments per line? If cannot,
never mind, i will slowly learning. 
~~~@@@###EZRA###@@@~~~
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Shouldn't the compiler call the method in the base class when the method with the same name is not declared as virtual?
Is this specific to VS2003?
#include <iostream>
using namespace std;
class mammal
{
public:
void walk () {cout << "mammal walks" << endl;}
protected:
mammal (bool pFacialhair) {facialhair = pFacialhair;};
bool facialhair;
virtual void takesaleak () {cout << "mammal takes a leak" << endl;}
};
class dog : public mammal
{
private:
bool takingapiss;
public:
dog() : mammal(true)
{
facialhair = true;
};
int legs;
void walk () {cout << "dog walks" << endl;}
void takesaleak () {cout << "dog takes a leak" << endl;}
};
void main ()
{ dog Fido;
Fido.walk(); //Error: mammal walks Actually the output is: dog walks
Fido.takesaleak(); //dog takes a leak
//Fido.takingapiss; // not allowed because it is a protected method
}
Error!
Jon
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jon_80 wrote: Shouldn't the compiler call the method in the base class when the method with the same name is not declared as virtual?
No.
Whether mammal's walk() is virtual or not, dog's walk() (if defined) will be called first, becuase fido object is constructed from dog class. And, mammal's walk() will not be called automatically. Virtual or not just controls whether this method can be overridden by the derived class. There is no confusing polymophism stuff here. If you want mammal's walk() to get called, either
1) you have to place it inside dog's walk(), or
2) if mammal's walk() is virtual, cast fido object using a mammal pointer and call walk().
Virtual destructor is an exception, which I assume you already know.
Best,
Jun
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Fido.walk();
you call Walk of Fido object .do u expect calling Walk of mammal?
if you wanna see virtual ! try these ,so you can see virtual how work!
first add this function just in mammal !
void ShowWalk(){ Walk()};
in main you try this code:
dog Fido;
mammal F;
Fido.ShowWalk();
F.ShowWalk();
so you can see polymorphism!
first output is : dog walks
second output is : mammal walks
is that your quastion?
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Um, that is not polymorphism.
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Polymorphism (and virtual) only have an effect when making function calls through pointers.
When you write Fido.walk() what do you expect to happen? dog has a walk() method, so that's what gets called.
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Michael Dunn wrote: Polymorphism (and virtual) only have an effect when making function calls through pointers.
valid for references,too.
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Hi friends,
My application consists of an interaction b/w the GUI and a RS-232 serial
port communication with a embedded device.
Initially we had a GUI menu based, where depending upon the user click
on the GUI , we used to send and receive the messages from the device.
Now, we have a requirement where we need to have a single start-up
dialog box instead of a menu for each selection.These means now we have
to show all the data from the device initially to the user.
For example say , when the user clicks View->ConfigDialog menu option
i have to pop-up a dialog box showing all the data from the device
Could you please help me regarding this.
Regards,
Veeresh
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int filenumber;
CString Pathname[20],Filename[20];
CFileDialog fd (TRUE,NULL,NULL,
OFN_HIDEREADONLY|OFN_ALLOWMULTISELECT
,"DCL FILE|*.DCL||");
if (fd.DoModal()==IDOK)
{
POSITION pos;
pos = fd.GetStartPosition();
filenumber = 0;
while (pos!=NULL)
{
Pathname[filenumber] = fd.GetNextPathName(pos);
TRACE("Pathname[%d]=%s\n",filenumber,
Pathname[filenumber]);
filenumber++;
}
When Open file more than 8 file together it will generate error.
Anybody know how to solve this problem?
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See
<br />
int filenumber = 0;<br />
POSITION pos;<br />
CString Pathname[20];<br />
char* lptstr = new char[256];<br />
<br />
CFileDialog m_FileDialog(1,0,0,OFN_ALLOWMULTISELECT | OFN_EXPLORER);<br />
<br />
m_FileDialog.m_ofn.nMaxFile = 256;<br />
m_FileDialog.m_ofn.lpstrFile = lptstr;<br />
m_FileDialog.m_ofn.lpstrFile[0] = NULL;<br />
<br />
m_FileDialog.DoModal();<br />
<br />
<br />
pos = m_FileDialog.GetStartPosition();<br />
while (pos!=NULL)<br />
{<br />
Pathname[filenumber] = m_FileDialog.GetNextPathName(pos);<br />
TRACE("Pathname[%d]=%s\n",filenumber,Pathname[filenumber]);<br />
filenumber++;<br />
}<br />
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Is there a way to know the color in which slider ticks should be painted by system?
Thanks.
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Does this[^]helps you ? Using option COLOR_SCROLLBAR.
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No, I've already checked all possible arguments to GetSysColor, no one match the color with which ticks painted... I expect this may be related to themes, because I work in WinXP, but how to be in this case? 
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Hello everyone,
I am going to design a Cache in C/C++ (memory cache). I have two different approaches to design/implement it, any comments will be appreciated.
Design 1, using a map (hashtable) to store key --> object pointer relationship (simple and straight forward);
Design 2, store real object or object pointer in a stack/linked list/queue/array as an internal storage data structure, then using a map (hashtable) as an external interface to mapping key --> index in the stack/linked list/queue/array; (in this design, when accessing an object, we need two times mapping, first mapping key to index in the stack/linked list/queue/array, then using the index to access the real object)
I am wondering any advantages or disadvantages of the two designs. Any better design approach suggestion will be appreciated.
thanks in advance,
George
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I would like to know how to inherit from classes and set protected properties of the base class within the derived class:
class mammal
{
protected:
mammal (bool pFacialhair) {facialhair = pFacialhair;};
bool facialhair;
};
class dog : public mammal
{
private:
bool takingapiss;
public:
dog()
{
facialhair = true;
};
int legs;
};
Error:
error C2512: 'mammal' : no appropriate default constructor available
Jon
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you dog class should be like this:
class dog : public mammal
{
private:
bool takinggapiss;
public:
dog(bool pFacialhair):mammal(pFacialhair)
{
....
}
...
}
when class dog inherits class mammal, the construction of an object of class mammal must be finished before the construction of the object of class dog. because you don't have a default constructor for class mammal, you have to provide an argument for the construction of mammal in the constructor of class dog.
I don't know if I have made myself clear.
-- modified at 7:08 Saturday 9th September, 2006
Thank you very much!!!
-------------------
I am learning C++ and English
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ewighell wrote: your dog class should be like this:
dog::dog(bool pFacialhair)
: mammal(pFacialhair) {
//...
}
or like this...
dog::dog()
: mammal(true) {
}
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First, UNICODE has been defined in my program.
Second, my CString involves Chinese characters as well as English letters.
the following piece of code runs correctly and the format of the resulted file "myTxt.txt" is Unicode
CFile file(_T("myTxt.txt"), CFile::modeCreate|CFile::modeWrite);
CArchive ar(&file, CArchive::store, 512);
CString str;
str = _T("Welcome 张三");
TRACE(str);
ar.WriteString(str);
however, the following piece of code dose not run correctly and the format of the resulted file "myTxt.txt" is ANSI
CFile file(_T("myTxt.txt"), CFile::modeCreate|CFile::modeWrite);
CArchive ar(&file, CArchive::store, 512);
CString str;
str = m_ListCtrl.getItemText(0,0);
TRACE(str);
ar.WriteString(str);
isn't it weird? anybody has any idea?
Thank you very much!!!
-------------------
I am learning C++ and English
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thank you
-------------------
I am learning C++ and English
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Hi
Can any one help me in storing integer values(3-4 values) which i get from a grid control in a Safearray....nd i need to use them again after storing....
This is the code which i wrote is this OK..
SAFEARRAY *intPixels;
SAFEARRAYBOUND rgsabound[1];
rgsabound[0].lLbound = 0;
rgsabound[0].cElements = 3;
intPixels = SafeArrayCreate(VT_I4,1,rgsabound);
int tempint_j = 0,tempint_p = 0;
for(int i = 0;i < 3;i = i+1)
{
CString tempStr; //Getting Values from Grid
tempStr = m_Grid.GetTextArray(i);
//convert values from String to int
//as they are from grid
int tempint_a = atoi(tempStr);
SafeArrayPutElement(intPixels,(long *)&tempint_j,(void *)&tempint_a);
tempint_j= tempint_j + 1;
}
Will the above code stores the values obtained from the Grid control(m_Grid) in the Safe Array.... if this stores the integer values in SafeArray pls tell me how to get them back to Use them.....?
Thanks
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Do you need to SafeArrayGetElement
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