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According to MSDN, getch is not standard C++, but _getch is ?
Christian Graus - Microsoft MVP - C++
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Hi all,
I developed windows form application using VC++.NET.
I have a check box that i need to know its status from another file. I can access it from the class file (using its name or this pointer) but i can't access it from another file within the project.
How can i do it?
I tried using the class namespace but no good.
Please help.
10'x
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Your check box should be private, you shouldn't be able to access it outside the class. It sounds like this is so. You should expose a public method to get the state of the checkbox.
Christian Graus - Microsoft MVP - C++
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I need help using fstream...
i need to read a text file that has multiple lines, each line has the syntax:
'fname lname 01 02 03 04 05 06 07 08 08 10'
that is a first name space last name space and 10 test scores (separated by spaces). I then have to move all the data from one file to another except i have to add the average of the 10 scores to the end of each line...
I can read the full text and display as it is from one file to the other. The problem is i can't read just the numbers in order to get the average...here's the code i have so far...
#include <iostream>
#include <cstdlib>
#include <fstream>
#include <iomanip>
using namespace std;
#define INPUTFILE "HW660-In.txt"
#define OUTPUTFILE "HW660-Out.txt"
void rwFiles(ifstream& inSource, ofstream& outSource);
bool goOn();
void main()
{
dispHeader();
do
{
ifstream inStudentRecord;
ofstream outStudentRecord;
inStudentRecord.open(INPUTFILE);
if (inStudentRecord.fail())
{
cout<<"Opening input file failed.\n";
exit(1);
};
outStudentRecord.open(OUTPUTFILE);
if (outStudentRecord.fail())
{
cout<<"Opening output file failed.\n";
exit(1);
};
rwFiles(inStudentRecord, outStudentRecord);
inStudentRecord.close();
outStudentRecord.close();
}while(goOn());
}
void dispHeader()
{
void rwFiles(ifstream& inSource, ofstream& outSource)
{
char next;
int iGrade = 0, oGrade = 0;
inSource.get(next);
while (!inSource.eof())
{
if(next == '\n')
{
cout<<" The End"; //this adds "The End" at the end of every line.
};
cout<<next;
outsource<<next;
="" insource.get(next);
="" };=""
}
bool="" goon()
{
="" char="" calcmore="Y" ;
="" bool="" goon="true;
" cout<<"would="" you="" like="" to="" continue?="" (y="" n)="" ";
="" cin="">>calcMore;
switch (calcMore)
{
case 'Y': case 'y': ;break;
case 'N': case 'n': default: goOn = false;
}
return goOn;
}
So basically all my code does is reads exactly what is in the input file and displays it to the screen as well as copies it to the output file.
noob in need of help...
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If you know the format of the file, you can use the << operator to read the file into the appropriate variable types, which in this case is two strings, and 10 numeric types. As it stands, you're reading a char at a time. The real alternative to what I've suggested is to use getline and then munch the string to extract the data by looking for spaces and using substr and atoi to convert to ints.
Christian Graus - Microsoft MVP - C++
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In those situation stringstream can be cool!
http://www.cplusplus.com/ref/iostream/stringstream/[^]
Here is the code to read one line in your file and to compute the average score.
std::ifstream ifs("FileName", std::ios::in);
char buffer[255];
ifs.getline(buffer, 255);
std::istringstream iss(buffer);
char n1[255];
char n2[255];
double grade, mean=0.0;
int nGrade = 0;
iss >> n1 >> n2;
for(; iss >> grade; ++nGrade) mean += grade;
mean /= nGrade;
ifs.close();
// end
Now figure a way to do this for the whole file 
Eric
Premature optimization is the root of all evil
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qfegd wrote: In those situation stringstream can be cool!
and (IMHO) utterly superfluous...
there is already and input stream open in the form of the input file stream
why read a line convert it to another input stream and then use operator>> on that stream
as the input text file is rigorously defined why not use >> directly on the input file stream?
operator>> is overloaded for the inbuilt types & defaults
to consuming white space and newlines (thanks Bjarne)
thus...
char n1[255];<br />
char n2[255];<br />
double total, mean, grade;<br />
int count = 10;
<br />
ifstream in_file(IN_NAME);
<br />
while(!in_file.eof()) {<br />
in_file >> n1 >> n2;<br />
total = 0.0;<br />
for(int i = 0, i < count, ++i) {<br />
in_file >> grade;<br />
total += grade;<br />
}<br />
mean = total / count;<br />
}
i will leave writing to the output file for you (it can all be fitted into the above loop in 3 lines)
if your input file might be dirty you could add
in_file.ignore(255,'\n');
to ignore upto 255 characters at the end of the line and any new line.
hope this helps?
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Christian Graus wrote: you can use the << operator to read
correction:
operator >> is overloaded to read the inbuilt types from an input stream
operator << is for writing to an output stream
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I could use some help with a file i/o issue. I'm using simple fstream objects to read in a Unicode file, search it for a particular string, and print the line if it contains that string.
Here's a snippet of my function:
getline(traceFile, buffer); //pass getline the file stream object and string buffer
pos = buffer.find(hr, 0); //set the position of string hr if found
if (pos != string::npos)
outFile << "Line Number " << count <<":"<< buffer <
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firstly a good unicode editor helps:
http://www.unipad.org/main/[^]
secondly the STL way is to convert to wide strings and streams
and (essential) use locales to 'imbue' them with the
ability to handle the unicode conversion that you desire
//include all the culture specific information you need
#include <locale>
//reveal the current locale
locale default_locale = wcout.getloc();<br />
cout << default_locale.name();
which if nothing has been imbued is C for classic
//create a new locale
locale french_locale("french");
//reveal its name
cout << french_locale.name();
//French_France.1253 in windows
//the names are non standard
//but the locales construct happily with intuitive language name or abbreviation
//see: http://www.microsoft.com/globaldev/nlsweb/default.asp[^]
//set a new locale
locale old_locale = wcout.imbue(french_locale);
use the widen and narrow methods to convert
and you should be away
a good code project article is here...
http://www.codeproject.com/vcpp/stl/upgradingstlappstounicode.asp?df=100&forumid=16224&exp=0&select=557556[^]
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Hi all,
How can I use C++ object in C code?
Let's say an object is implemented by others in C++, but I want to use this object in my C code.
Is this possible?
Is there any trick I can use?
Thanks in advance!
--Tosh
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I doubt this is possible....
even if you know the memory schema of an allocated object, you won't be able to access the members (for instance by dereferenciate a pointer to the address needed) if they were defined private or protected...
TOXCCT >>> GEII power
[toxcct][VisualCalc]
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You can do the following, create a .cpp file and put a extern "C" function into it. This function can access your CPP object and can also be called from your C file.
foo.cpp
--------
<br />
extern "C" int call_to_obj ()<br />
{<br />
return myObject.SomeMethod ();<br />
}<br />
I hope that helps.
-- modified at 6:12 Tuesday 17th January, 2006
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i am a novice in game programming and i want to ask how
a program can read two keys simultaneously.
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Direct Input, part of DirectX.
Christian Graus - Microsoft MVP - C++
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Train free @Microsoft
Got to this link and register free for
training your self for VS2005
https://www.microsoftelearning.com/visualstudio2005/
or
http://www.financialexpress.com/latest_full_story.php?content_id=107645
Microsoft dont give anything free except training
Vikas Amin
Embin Technology
Bombay
vikas.amin@embin.com
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Hello...
I am having trouble setting the initial size of my SDI application. I thought that I would be able to override the PreCreateWindow() function in my MainFrame and reset the values of the CREATESTRUCT like this:
BOOL CMainFrame::PreCreateWindow(CREATESTRUCT& cs)
{
cs.cx = 1000;
cs.cy = 730;
if(!CFrameWnd::PreCreateWindow(cs))
return false;
return TRUE;
}
However, this does not work. I also tried the MoveWindow() function and SetWindowPos() function in the OnSize of CMainFrame. That looks like this..
void CMainFrame::OnSize(UINT nType, int cx, int cy)
{
CFrameWnd::OnSize(nType, cy, cy);
if(!m_ResizeFlag)
{
MoveWindow(300, 300, 1000, 730);
m_ResizeFlag = true;
}
}
This did not work, either..
Any help would be MUCH appreciated!
Thanks in advance!
~SheriMarie
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I add #include <windows.h> to stdafx.h file in windows form application and it dosent want to compile the project issuing this:
error C2039: 'GetObjectW' : is not a member of 'System::Resources::ResourceManager'
for this piece of code:
this->Icon = (__try_cast<system::drawing::icon *="">(resources->GetObject(S"$this.Icon")));
I just assigned new icon to my application and this code was added atomatically, but without #include <windows.h> it is compiled normally?
9ine
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undefine GetObject and define a GetObject_T macro for calling the GetObjectA and GetObjectW API.
My blogs:
http://blog.joycode.com/jiangsheng
http://blog.csdn.net/jiangsheng
http://bloglines.com/public/jiangsheng
Command what is yours
Conquer what is not
---Kane
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would you please indicate where should I undefine this macro and how to define another GetObject_T
9ine
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another error with this code?
MessageBox::Show(this, S"err");
error C2653: 'MessageBoxW' : is not a class or namespace name
9ine
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#undef MessageBox
#undef GetObject
My blogs:
http://blog.joycode.com/jiangsheng
http://blog.csdn.net/jiangsheng
http://bloglines.com/public/jiangsheng
Command what is yours
Conquer what is not
---Kane
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Hi Folks,
I got a Wrapper Dll around a native C++ static library. In .NET 1.1 this
worked fine. When moving to .NET 2.0 I get a couple of unresolved externals /
linker errors:
Error 16 error LNK2028: unresolved token (0A000007) "extern "C" void
__clrcall ___CxxCallUnwindDtor(void (__clrcall*)(void *),void *)"
(?___CxxCallUnwindDtor@@$$J0YMXP6MXPAX@Z0@Z) referenced in function "public:
virtual __thiscall std::logic_error::~logic_error(void)"
(??1logic_error@std@@$$FUAE@XZ) Parameter.obj
Error 17 error LNK2028: unresolved token (0A000007) "extern "C" void
__clrcall ___CxxCallUnwindDtor(void (__clrcall*)(void *),void *)"
(?___CxxCallUnwindDtor@@$$J0YMXP6MXPAX@Z0@Z) referenced in function "public:
__thiscall std::bad_alloc::bad_alloc(char const *)"
(??0bad_alloc@std@@$$FQAE@PBD@Z) Imagic.obj
Error 18 error LNK2028: unresolved token (0A000008) "extern "C" void
__clrcall ___CxxCallUnwindDtor(void (__clrcall*)(void *),void *)"
(?___CxxCallUnwindDtor@@$$J0YMXP6MXPAX@Z0@Z) referenced in function "public:
virtual __thiscall std::logic_error::~logic_error(void)"
(??1logic_error@std@@$$FUAE@XZ) Align2D.obj
Error 19 error LNK2028: unresolved token (0A000347) "void __clrcall `eh
vector destructor iterator'(void *,unsigned int,int,void (__clrcall*)(void
*))" (??_M@$$FYMXPAXIHP6MX0@Z@Z) referenced in function "public: virtual void
* __thiscall std::logic_error::`vector deleting destructor'(unsigned int)"
(??_Elogic_error@std@@$$FUAEPAXI@Z) Parameter.obj
Error 20 error LNK2028: unresolved token (0A0003D3) "void __clrcall `eh
vector destructor iterator'(void *,unsigned int,int,void (__clrcall*)(void
*))" (??_M@$$FYMXPAXIHP6MX0@Z@Z) referenced in function "public: virtual void
* __thiscall std::bad_alloc::`vector deleting destructor'(unsigned int)"
(??_Ebad_alloc@std@@$$FUAEPAXI@Z) Imagic.obj
Error 21 error LNK2028: unresolved token (0A000358) "void __clrcall `eh
vector destructor iterator'(void *,unsigned int,int,void (__clrcall*)(void
*))" (??_M@$$FYMXPAXIHP6MX0@Z@Z) referenced in function "public: virtual void
* __thiscall std::logic_error::`vector deleting destructor'(unsigned int)"
(??_Elogic_error@std@@$$FUAEPAXI@Z) Align2D.obj
Error 22 error LNK2001: unresolved external symbol "?.cctor@@$$FYMXXZ"
(?.cctor@@$$FYMXXZ) Align2D.obj
Error 23 error LNK2001: unresolved external symbol "?.cctor@@$$FYMXXZ"
(?.cctor@@$$FYMXXZ) AssemblyInfo.obj
Error 24 error LNK2001: unresolved external symbol "?.cctor@@$$FYMXXZ"
(?.cctor@@$$FYMXXZ) Imagic.obj
Error 25 error LNK2001: unresolved external symbol "?.cctor@@$$FYMXXZ"
(?.cctor@@$$FYMXXZ) Parameter.obj
Error 26 error LNK2019: unresolved external symbol "extern "C" void
__clrcall ___CxxCallUnwindDtor(void (__clrcall*)(void *),void *)"
(?___CxxCallUnwindDtor@@$$J0YMXP6MXPAX@Z0@Z) referenced in function "public:
virtual __thiscall std::logic_error::~logic_error(void)"
(??1logic_error@std@@$$FUAE@XZ) Align2D.obj
Error 27 error LNK2001: unresolved external symbol "extern "C" void
__clrcall ___CxxCallUnwindDtor(void (__clrcall*)(void *),void *)"
(?___CxxCallUnwindDtor@@$$J0YMXP6MXPAX@Z0@Z) Imagic.obj
Error 28 error LNK2001: unresolved external symbol "extern "C" void
__clrcall ___CxxCallUnwindDtor(void (__clrcall*)(void *),void *)"
(?___CxxCallUnwindDtor@@$$J0YMXP6MXPAX@Z0@Z) Parameter.obj
Error 29 error LNK2019: unresolved external symbol "void __clrcall `eh
vector destructor iterator'(void *,unsigned int,int,void (__clrcall*)(void
*))" (??_M@$$FYMXPAXIHP6MX0@Z@Z) referenced in function "public: virtual void
* __thiscall std::logic_error::`vector deleting destructor'(unsigned int)"
(??_Elogic_error@std@@$$FUAEPAXI@Z) Align2D.obj
Error 30 error LNK2001: unresolved external symbol "void __clrcall `eh
vector destructor iterator'(void *,unsigned int,int,void (__clrcall*)(void
*))" (??_M@$$FYMXPAXIHP6MX0@Z@Z) Imagic.obj
Error 31 error LNK2001: unresolved external symbol "void __clrcall `eh
vector destructor iterator'(void *,unsigned int,int,void (__clrcall*)(void
*))" (??_M@$$FYMXPAXIHP6MX0@Z@Z) Parameter.obj
Error 32 fatal error LNK1120: 9 unresolved externals Debug\empDll.dll
In my .NET 1.1 Project I had to make the following Linker Settings to build
the DLL:
1.) Additional Dependencies: mscoree.lib msvcrt.lib (or msvcrtd.lib for
debug version) mystaticlib.lib
2.) Ignore Specific Library: nochkclr.obj
3.) Force Symbol Reference: __DllMainCRTStartup@12
In my Wrapper Classes I had to add the following:
#using <mscorlib.dll>
using namespace System;
using namespace System::Runtime::InteropServices;
This does not work any longer with the new Visual Studio and the new .NET
Framework.
The only article that I was able to find on this subject:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnvs05/html/TransGuide.asp
Doesn´t mention Linker settings at all.
Could anybody please help me or tell me where to go for further reading?
Thanks in Advance for your efforts.
Chucker
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Building Q3.obj.
Building WeekOne.exe.
POLINK: error: Symbol '_main' is multiply defined.
*** Error code: 1 ***
Done.
Im doing this simple program and i got this error after executing. Below is the code. Please help.
_____________________________________________________________________________
#include <stdio.h>
int main ( ) {
int gross_sales;
int earnings;
int counter;
earnings = 200;
counter = 0;
while ( counter !=7 ){
printf("\nEnter Gross Sales:");
scanf("%d", &gross_sales );
counter = counter + 1;
}
earnings = 200 + 0.9*gross_sales;
printf("\nTotal earnings for last week is %d:\n", earnings);
return 0;
}
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did you created an empty project or used the wizard ?
if you've choosen the later, the wizard may have already defined the main() function somewhere in the code - as the error tells us.
one question though, what was the file #included ? stdio.h ?
TOXCCT >>> GEII power
[toxcct][VisualCalc]
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