수정이 필요함
#include 
#include 

LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);
HINSTANCE g_hInst;
LPSTR lpszClass="Calculator";

int APIENTRY WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance
		  ,LPSTR lpszCmdParam,int nCmdShow)
{
	HWND hWnd;
	MSG Message;
	WNDCLASS WndClass;
	g_hInst=hInstance;
	
	WndClass.cbClsExtra=0;
	WndClass.cbWndExtra=0;
	WndClass.hbrBackground=CreateSolidBrush(RGB(235,235,235));
	WndClass.hCursor=LoadCursor(NULL,IDC_ARROW);
	WndClass.hIcon=LoadIcon(NULL,IDI_APPLICATION);
	WndClass.hInstance=hInstance;
	WndClass.lpfnWndProc=(WNDPROC)WndProc;
	WndClass.lpszClassName=lpszClass;
	WndClass.lpszMenuName=NULL;
	WndClass.style=CS_HREDRAW | CS_VREDRAW;
	RegisterClass(&WndClass);

	hWnd=CreateWindow(lpszClass,lpszClass,WS_CAPTION | WS_MINIMIZEBOX | WS_SYSMENU,
		  CW_USEDEFAULT,CW_USEDEFAULT,302,226,
		  NULL,(HMENU)NULL,hInstance,NULL);
	ShowWindow(hWnd,nCmdShow);
	
	while(GetMessage(&Message,0,0,0)) {
		TranslateMessage(&Message);
		DispatchMessage(&Message);
	}
	return Message.wParam;
}

//컨트롤값 정의
#define ID_SCREEN (HMENU)100

#define ID_C	(HMENU)1
#define	ID_CE	(HMENU)2
#define ID_BS	(HMENU)3

#define ID_MA   (HMENU)4
#define ID_MC	(HMENU)5
#define ID_MR	(HMENU)6
#define ID_MS	(HMENU)7

#define ID_B0	(HMENU)8
#define ID_B1	(HMENU)9
#define ID_B2	(HMENU)10
#define ID_B3	(HMENU)11
#define ID_B4	(HMENU)12
#define ID_B5	(HMENU)13
#define ID_B6	(HMENU)14
#define ID_B7	(HMENU)15
#define ID_B8	(HMENU)16
#define ID_B9	(HMENU)17

#define ID_DIV	(HMENU)18
#define ID_MUL	(HMENU)19
#define ID_SUB	(HMENU)20
#define ID_ADD	(HMENU)21

#define ID_SQRT	(HMENU)22
#define ID_MOD	(HMENU)23
#define ID_RVS	(HMENU)24
#define ID_EQL	(HMENU)25

#define ID_SIGN	(HMENU)26
#define ID_DOT	(HMENU)27

//현재 연산 종류
#define ADD 101
#define SUB	102
#define MUL	103
#define DIV	104
#define INI 105

//버튼 눌림 함수 선언
void ClickedC();

HWND hScreen;

long double lVal=0,lTemp=0;	//계산값, 메모리값
int iStatus=INI;	//현재 연산의 종류
bool bDot=FALSE;	//소수점 on,off
char strVal[34];

LRESULT CALLBACK WndProc(HWND hWnd,UINT iMessage,WPARAM wParam,LPARAM lParam)
{
	switch(iMessage) {
	case WM_CREATE:
		//스크린
		hScreen=CreateWindow("edit","0",WS_CHILD | WS_VISIBLE | WS_BORDER | SS_WHITERECT | ES_RIGHT,
			5,5,282,20,hWnd,ID_SCREEN,g_hInst,NULL);

		//버튼생성
		//C
		CreateWindow("button","C",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			212,38,75,25,hWnd,ID_C,g_hInst,NULL);
		//CE
		CreateWindow("button","CE",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			135,38,75,25,hWnd,ID_CE,g_hInst,NULL);
		//Backspace
		CreateWindow("button","Backspace",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			58,38,75,25,hWnd,ID_BS,g_hInst,NULL);

		//MemoryClear
		CreateWindow("button","MC",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			5,75,35,25,hWnd,ID_MC,g_hInst,NULL);
		//MemoryRead
		CreateWindow("button","MR",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			5,104,35,25,hWnd,ID_MR,g_hInst,NULL);
		//MemorySave
		CreateWindow("button","MS",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			5,133,35,25,hWnd,ID_MS,g_hInst,NULL);
		//MemoryAdd
		CreateWindow("button","M+",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			5,162,35,25,hWnd,ID_MA,g_hInst,NULL);

		//Sqrt
		CreateWindow("button","sqrt",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			252,75,35,25,hWnd,ID_SQRT,g_hInst,NULL);
		//%
		CreateWindow("button","%",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			252,104,35,25,hWnd,ID_MOD,g_hInst,NULL);
		//1/x
		CreateWindow("button","1/x",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			252,133,35,25,hWnd,ID_RVS,g_hInst,NULL);
		//=
		CreateWindow("button","=",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			252,162,35,25,hWnd,ID_EQL,g_hInst,NULL);

		//'/'
		CreateWindow("button","/",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			212,75,35,25,hWnd,ID_DIV,g_hInst,NULL);
		//*
		CreateWindow("button","*",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			212,104,35,25,hWnd,ID_MUL,g_hInst,NULL);
		//-
		CreateWindow("button","-",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			212,133,35,25,hWnd,ID_SUB,g_hInst,NULL);
		//+
		CreateWindow("button","+",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			212,162,35,25,hWnd,ID_ADD,g_hInst,NULL);

		//9
		CreateWindow("button","9",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			172,75,35,25,hWnd,ID_B9,g_hInst,NULL);
		//8
		CreateWindow("button","8",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			132,75,35,25,hWnd,ID_B8,g_hInst,NULL);
		//7
		CreateWindow("button","7",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			92,75,35,25,hWnd,ID_B7,g_hInst,NULL);
		//6
		CreateWindow("button","6",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			172,104,35,25,hWnd,ID_B6,g_hInst,NULL);
		//5
		CreateWindow("button","5",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			132,104,35,25,hWnd,ID_B5,g_hInst,NULL);
		//4
		CreateWindow("button","4",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			92,104,35,25,hWnd,ID_B4,g_hInst,NULL);
		//3
		CreateWindow("button","3",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			172,133,35,25,hWnd,ID_B3,g_hInst,NULL);
		//2
		CreateWindow("button","2",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			132,133,35,25,hWnd,ID_B2,g_hInst,NULL);
		//1
		CreateWindow("button","1",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			92,133,35,25,hWnd,ID_B1,g_hInst,NULL);
		//0
		CreateWindow("button","0",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			92,162,35,25,hWnd,ID_B0,g_hInst,NULL);

		//'+/-'
		CreateWindow("button","+/-",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			132,162,35,25,hWnd,ID_SIGN,g_hInst,NULL);
		//.
		CreateWindow("button",".",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
			172,162,35,25,hWnd,ID_DOT,g_hInst,NULL);
		return 0;

	case WM_KEYDOWN:
		switch(wParam){
			case 46:	//Delete, CE처리
			case 27:	//ESC, C처리
				ClickedC();
				return 0;
		}
		if(lVal==(int)lVal){	//정수일 때
			switch(wParam){
			case 49:
			case 97:
			case 35:
				lVal=lVal*10+1;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			case 50:
			case 98:
			case 40:
				lVal=lVal*10+2;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			case 51:
			case 99:
			case 34:
				lVal=lVal*10+3;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			case 52:
			case 100:
			case 37:
				lVal=lVal*10+4;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			case 53:
			case 101:
			case 12:
				lVal=lVal*10+5;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			case 54:
			case 102:
			case 39:
				lVal=lVal*10+6;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			case 55:
			case 103:
			case 36:
				lVal=lVal*10+7;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			case 56:
			case 104:
			case 38:
				lVal=lVal*10+8;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			case 57:
			case 105:
			case 33:
				lVal=lVal*10+9;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			case 48:
			case 96:
			case 45:
				lVal=lVal*10+0;
				sprintf(strVal,"%G",lVal);
				SetWindowText(hScreen,strVal);
				return 0;
			}
		}//정수 일 때
		return 0;
	case WM_COMMAND:
		switch(wParam){
		case ID_SIGN:
			lVal=-lVal;
			sprintf(strVal,"%G",lVal);
			SetWindowText(hScreen,strVal);
			SetFocus(hWnd);
			return 0;
		case ID_CE:	//방금 입력한 수만 지움
		case ID_C:	//메모리 다 지움
			ClickedC();
			SetFocus(hWnd);
			return 0;
		}

		//버튼눌림, lVal이 정수 일 때
		if(lVal==(int)lVal){
			switch(wParam){
				case ID_B1:
					lVal=lVal*10+1;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
				case ID_B2:
					lVal=lVal*10+2;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
				case ID_B3:
					lVal=lVal*10+3;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
				case ID_B4:
					lVal=lVal*10+4;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
				case ID_B5:
					lVal=lVal*10+5;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
				case ID_B6:
					lVal=lVal*10+6;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
				case ID_B7:
					lVal=lVal*10+7;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
				case ID_B8:
					lVal=lVal*10+8;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
				case ID_B9:
					lVal=lVal*10+9;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
				case ID_B0:
					lVal=lVal*10+0;
					sprintf(strVal,"%G",lVal);
					SetWindowText(hScreen,strVal);
					SetFocus(hWnd);
					return 0;
			}
		}
	case WM_DESTROY:
		PostQuitMessage(0);
		return 0;
	}
	return(DefWindowProc(hWnd,iMessage,wParam,lParam));
}

//버튼눌림 함수 정의
void ClickedC(){	//계산기 메모리 초기화
	lVal=0;
	sprintf(strVal,"%G",lVal);
	SetWindowText(hScreen,strVal);
}
Posted by 공돌이pooh
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