C++ :: Function Keys (F1-F12) Encountered A Logic Bug
Feb 27, 2014
I was developing an exercise program for myself (note: not a project in school) to enhance my programming skills in C++ then I encountered a "logic bug" (that's how I call it :D ) I think. I googled stuffs I need to know and ended up to post my question here.
Here's the scene:
1. When using GetAsyncKeyState I can capture Function Keys [F1-F12, etc..]
2. While doing and having fun to my exercise program, I suddenly noticed that whatever key I pressed from the keyboard {example: asdfkj], it keeps the keys entered and brings to a "field" that accepts user input.
What you should do...
1. Press any key (example: asdfisdjfisdjff) then proceed to press F1. And see what happens. I don't know how to erase what I have entered before pressing F1.
here's the code.
#include <cstdlib>
#include <iostream>
#include <windows.h>
#include <string>
using namespace std;
void gotoxy();
void gotoxy( int column, int line ) {
[code]....
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Oct 23, 2012
Say I have a dll that performs some mathematical parsing and calculations. The calling function is only a single C -linkage wrapper function in the dll. I can anticipate likely errors and program the dll methods to do several things when an anticipated error is encountered. (For now, let's not worry about unanticipated errors).
1 - send an error message to the user application using WM_COPYDATA
2 - throw an exception (assuming the calling app has used the try catch scenario)
3 - try to gracefully recover from the error within the dll and keep on going (jump to some safe place - but how ??)
4 - don't throw an exception from within the dll but halt the program (not very nice - the user won't know what happened)
Previous discussions on the matter have predominantly expressed the opinion that it is bad to throw exceptions from within a dll.
Long ago there was in use setjmp.h and something like
Code: if(setjmp(e_buf)) return -1;
But I believe this was only for old C applications - I'm not really sure. But at least someone back then recognized the need for getting back to a safe place in a process.
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Mar 31, 2012
I found this method
Code:
TCHAR win_getch()
(below) on a website which is used for printing the characters as the keys on keyboard are hit i-e without hitting the ENTER key. This method is used in a while loop like this
Code:
while ((c = win_getch()) != 13)
{}
I wanted to know why is the character compared to
Code:
13
i-e
Code:
if((c = win_getch()) != 13) then do something
Code:
/**
* This function will simulate the getch() function from conio.h.
* Note that this does not work for special keys like F1-F12, arrow keys,
* even the ESC key does not seem to work with this function.
* @return TCHAR read from input buffer.
*/
TCHAR win_getch() {
DWORD mode;
TCHAR theChar = 0;
[code]....
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[Code]...
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key1 ----|
key2 ----|--------- value1
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private void Navigate(object sender, KeyEventArgs e) {
TextBox input = (TextBox)sender;
string nextBox = input.Name.ToString();
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[Code] ....
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Code:
1
121
12321
1234321
123454321 EDIT:
the above pyramid looks like a doom.i.e 1-5 will be in center.1-4(L)1-3(L)1-2(L)1(L) similarly 1-4(R) 1-3(R) 1-2(R) 1(R)
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Code:
for (int i = 1; i <= 5; i++)
{
//int l = 1;
[Code]....
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Stack stack;
Maze maze;
Lock taken;
// Monster monster;
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[Code] ....
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[Code] ...
My accompanying class declarations can be found here : [URL] ....
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header
//date.h header
#include <iostream>
#include <string>
using namespace std;
enum DateFormat {numeric, standard, alternative};
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file containing words to search for=external file
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#include <vector>
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[Code] ....
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Typedef.hpp
Code:
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#define TYPEDEF_HPP
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[Code] ....
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I am trying to find out how I can print the least common 10 sets. I think if there are any set which have not been picked I would have to print all of those because logically they would all be equal, then print sequentially the sets least picked up to 10.
I have pseudocode which I am sure is wrong but will post it just to show that I am trying. My first attempt was to add the numbers but quickly realized that that wouldn't work ...
5 Nums Pseudocode
Code:
Read Nums
Parse Into Ints
Make Array [185] //39+38+37+36+35 The highest the numbers added together can go
//LOGIC
[Code] ....
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Code:
struct Event {
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int type;
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Aug 16, 2014
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12345 870
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struct trans{
[Code].....
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{
[Code]....
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I have a hit a snag in a number guessing game program. I was given a half-completed program and told to use functions to complete the missing pieces. It looks unwieldy, but this is how it is supposed to be. I have temporarily made the random guess value visible for troubleshooting purposes.
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#include <stdlib.h>
using namespace std;
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[code]....
The issue lies within this piece of code:
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}
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[Code] ....
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and also
type mismatch in parameter in function sort(int,int)
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clrscr();
[Code] .....
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Feb 11, 2013
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Code:
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}
[code]....
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