Adding items to a list
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even in C# you need to have a ToString method. How would C++ what you actually want to print. That being said. What do you want to print? The id? In that case you could have an implicit cast to QString like:
@
class ProcInfo
{
public:
//code
operator QString() const
{
return QString::number(id);
}
};
@
or you could call QString::number in the loop instead of adding an implicit cast function:
@
ui->myList->addItem(QString::number((*p).id));
@ -
[quote author="loladiro" date="1312196973"]even in C# you need to have a ToString method. How would C++ what you actually want to print. [/quote]
No you don't in C#, because when you create a class it automatically has a base ToString() method which is automatically used in certain controls like listboxes without being called (although the string would be simply the class name unless you override the method) I assumed C++ would be no different but clearly it is.
Thanks for the help.
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The posts must have crossed in the air ;). The QString() const method is an "explicit coversion operator":http://msdn.microsoft.com/en-us/library/ts48df3y(v=vs.80).aspx . However, be aware that there are also many bugs that may follow from the misuse of this laguage feature.
EDIT: you can use it just like ou would in C# (i.e. without doing anything special)
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Actually there are more compile errors I should have mentioned which are most likely causing this:
error: no match for 'operator=' in 'p = procList.std::list<_Tp, _Alloc>::begin with _Tp = int, _Alloc = std::allocator<int>'
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Sorry but I can't reproduce. This all works:
@
class ProcInfo
{
public:
int id;
ProcInfo() : id(1234)
{}
operator QString() const
{
return QString::number(id);
}
};void print(QString print)
{
qDebug() << print;
}int main(int argc, char *argv[])
{
QApplication a(argc, argv);QList< ProcInfo > list1; list1 << ProcInfo(); QList< ProcInfo >::const_iterator i = list1.begin(); std::list< ProcInfo > list2; list2.push_back(ProcInfo()); std::list< ProcInfo >::const_iterator i2 = list2.begin(); print(*i2); print (*(i)); QListWidget widget; widget.addItem(*i); std::list< ProcInfo >::const_iterator p = list2.begin(); for (p=list2.begin();p!=list2.end(); ++p) { widget.addItem(*p); } widget.show(); const ProcInfo p2; print(p2); return a.exec();}
@ -
Ok I've managed to get rid of all compile errors except this one:
error: expected type-specifier before 'QString'
And the error points to the operator:
@
class ProcInfo
{
public:
HANDLE Proc;
DWORD Base;
int ID;
operator QString() const
{
return QString::number(ID);
}
};@ -
That fixed that but now I have another problem /sigh.
I have declared std::list<ProcInfo> procList; inside a header file, and that header file is included in the main cpp file which I am doing this all in, however I get error:
error: multiple definition of `procList'
There is definitely only 1 definition and it's inside the h file so I'm a little confused, maybe c++ isn't for me :(
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proc.h
@
#include <windows.h>
#include <list>
#include <QString>#ifndef PROC_H
#define PROC_H#endif // PROC_H
class ProcInfo
{
public:
HANDLE Proc;
DWORD Base;
int ID;
operator QString() const
{
return QString::number(ID);
}
};std::list< ProcInfo > procList;
bool createProcessList();
DWORD GetModuleBase(LPSTR lpModuleName, DWORD dwProcessId);
@proc.cpp
@
#include <windows.h>
#include <iostream>
#include <string>
#include <tlhelp32.h>
#include "proc.h"
#include "misc.h"using namespace std;
bool createProcessList()
{
PROCESSENTRY32 entry;
entry.dwSize = sizeof(PROCESSENTRY32);HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, NULL); if (Process32First(snapshot, &entry;) == TRUE) { while (Process32Next(snapshot, &entry;) == TRUE) { char *procName; strcpy_wc(procName, entry.szExeFile); if (stricmp(procName, "pol") == 0) { ProcInfo *p = new ProcInfo(); p->Proc = OpenProcess(PROCESS_ALL_ACCESS,FALSE,entry.th32ProcessID); p->ID = entry.th32ProcessID; p->Base = GetModuleBase("test.dll", entry.th32ProcessID); procList.push_back(*p); } } if (procList.empty()) return false; return true; } CloseHandle(snapshot); return 0;}
DWORD GetModuleBase(LPSTR lpModuleName, DWORD dwProcessId)
{
MODULEENTRY32 lpModuleEntry = {0};
HANDLE hSnapShot = CreateToolhelp32Snapshot( TH32CS_SNAPMODULE, dwProcessId );
if(!hSnapShot)
return NULL;
lpModuleEntry.dwSize = sizeof(lpModuleEntry);
BOOL bModule = Module32First( hSnapShot, &lpModuleEntry; );
while(bModule)
{
char *foundModule;
strcpy_wc(foundModule, lpModuleEntry.szModule);
if(!strcmp( foundModule, lpModuleName ) )
{
CloseHandle( hSnapShot );
return (DWORD)lpModuleEntry.modBaseAddr;
}
bModule = Module32Next( hSnapShot, &lpModuleEntry; );
}
CloseHandle( hSnapShot );
return NULL;
}
@That error points to line 11 in proc.cpp.
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Well, my first comment is: fix your "include guards":http://en.wikipedia.org/wiki/Include_guard
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Yes! Let me explain. In C (and C++) an #include directive will include the file regardless of whether it has been included before. You can litterally compare this to copy'n'past-ing the header file into the source code whenever there is an #include directive. The include guards are used to make sure every header file is only included once. E.g. if your header file would usually be
@
class Dummy
{};
@
you'd have to use
@
#ifndef DUMMY_H //i.e. if dummy.h has never been included before
#define DUMMY_H //remember that it has been includedclass Dummy
{};#endif //endif after all statements
@
In your case the include guards have to enclose all of your statements (the header files not necessarily because they have their own include guards, but it's usually best to have the include guards be the first and last satements in your header files)