WindowsAPI编程简单的计算器

末蓝、 2024-04-17 05:54 53阅读 0赞

###                                                    WindowsAPI编程 简单的计算器 ###

一、简述

记--使用WindowsAPI开发图形界面应用--简单的计算器。

例子：链接: https://pan.baidu.com/s/1SDg5RByN4xQohoi-ao8Wzg 提取码: kv42

二、效果

![20190920182033285.gif][]

![2019092018205595.png][]

三、工程结构

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmZlaWJ1eWk_size_16_color_FFFFFF_t_70][]

四、源文件

main.cpp文件

#define _CRT_SECURE_NO_WARNINGS  //有一些函数有新的安全版本，使用就之前的会报警告
    #include <windows.h>
    #include "resource.h"
    #include <stdio.h>
    
    #define EXP_MAX_LEN 22
    
    char gSign[3] = {0};//运算符×÷+-
    
    //判断指定的字符是否是运算符
    int IsASign(const char* _char,unsigned char _flag)
    {
    	if(NULL == _char)
    	{
    		return 0;
    	}
    
    	if(1 == _flag)//ASCII模式
    	{
    		if(_char[0] == '+' )
    		{
    			return 3;
    		}
    		else if(_char[0] == '-' )
    		{
    			return 4;
    		}
    	}	
    	
    	if(strlen(_char)>1)//×÷是中文字符，占2个字节
    	{
    		if(_char[0] == "×"[0] && _char[1] == "×"[1] )
    		{
    			return 1;
    		}
    
    		if(_char[0] == "÷"[0] && _char[1] == "÷"[1] )
    		{
    			return 2;
    		}
    
    		if(2 == _flag)//判断最后一个字符的时候
    		{
    			if(_char[1] == '+' )
    			{
    				return 3;
    			}
    			else if(_char[1] == '-' )
    			{
    				return 4;
    			}
    		}	
    	}
    
    	return 0;
    }
    
    //判断表达式是否含有运算符
    int ExpIsHasSign(const char* _exp)
    {
    	int i;
    	int len;
    	if(NULL != _exp)
    	{
    		len = strlen(_exp);
    		for(i=0; i<len; i++)
    		{
    			if(IsASign(&(_exp[i]),1)>0)
    			{
    				return 1;
    			}
    		}
    	}
    	return 0;
    }
    
    //计算两个运算数的结果
    int GetResult(long long _leftVal, long long _rightVal, char _sign, long long* _result)
    {
    	int ret = 0;
    	if(_sign == '*')
    	{
    		*_result = _leftVal*_rightVal;
    		ret = 1;
    	}
    	else if(_sign == '/')
    	{
    		if(0 != _rightVal)
    		{
    			*_result = _leftVal/_rightVal;
    			ret = 1;
    		}
    	}
    	else if(_sign == '+')
    	{
    		*_result = _leftVal+_rightVal;
    		ret = 1;
    	}
    	else if(_sign == '-')
    	{
    		*_result = _leftVal-_rightVal;
    		ret = 1;
    	}
    	return ret;
    }
    
    //判断字符串最后一个字符是否是运算符
    int StrLastCharIsSign(char* _str)
    {
    	UINT len = 0;
    	if(NULL == _str)
    	{
    		return 0;
    	}
    
    	len = strlen(_str);
    	if(len>512)
    	{
    		len = 511;
    		_str[512] = '\0';
    	}
    	if(len>0)
    	{
    		if(IsASign(&(_str[len-1]),1)>0 )
    		{
    			return 1;
    		}
    		if(len>1)
    		{
    			if(IsASign(&(_str[len-2]),2)>0)
    			{
    				return 1;
    			}
    		}
    	}
    	return 0;
    }
    
    //判断表达式最后一个字符是否是运算符
    int LastCharIsSign(HWND _hwndDlg, int _nID)
    {
    	char buf[512] = {0};
    	GetDlgItemText(_hwndDlg, _nID, buf, sizeof(buf));
    	return StrLastCharIsSign(buf);
    }
    
    //判断一个字符是否是数字
    char IsANum(const char _ch)
    {
    	if(_ch>= '0' && _ch<='9')
    	{
    		return _ch;
    	}
    	return -1;
    }
    
    //将字符串形式的运算数转化为数字
    int StrToDec(const char* strNum, long long* num)
    {
    	if(NULL == strNum)
    	{
    		return -1;
    	}
    	*num = 0;
    	int len = strlen(strNum);
    	int i;
    	for(i=0; i<len; i++)
    	{
    		if(IsANum(strNum[i])>0)
    		{
    			*num = (*num*10) + (strNum[i] - '0');
    		}
    	}
    	return 0;
    }
    
    //计算表达式结果
    int GetExpResult(HWND hwndDlg, int nID)
    {
    	char buf[512] = {0};
    	GetDlgItemText(hwndDlg, nID, buf, sizeof(buf));
    	char* bufPtr = buf;
    	
    	int len = strlen(gSign);
    	if(len<=0)
    	{
    		return -1;
    	}
    
    	int isNagtive = 0;//标识左值是否是负数
    	if(buf[0] == '-')
    	{
    		isNagtive = 1;
    		bufPtr++;
    	}
    
    	len = strlen(bufPtr);
    	if(len<3)
    	{
    		return -2;
    	}
    	
    
    	char* signPtr = strstr(bufPtr, gSign);
    	if(NULL != signPtr && 0 == StrLastCharIsSign(bufPtr))//有运算符并且不是最后一个字符的（也就是用户输入了两个运算数和一个运算符了才进行运算）
    	{
    		int signIndex = strlen(signPtr);
    		char chLeftVal[512] = {0};//左值
    		char chRightVal[512] = {0};//右值
    		long long numLeftVal = 0;
    		long long numRightVal = 0;
    		long long result = 0;//结果
    		int sign = IsASign(gSign,1);
    		
    		memcpy(chLeftVal,bufPtr,len-signIndex);
    		memcpy(chRightVal,&bufPtr[len-signIndex+1+(sign/3+1)%2],signIndex-strlen(gSign));
    
    		int ret1, ret2, ret3 = 0;
    		ret1 = StrToDec(chLeftVal, &numLeftVal);
    		ret2 = StrToDec(chRightVal, &numRightVal);
    		if(1 == isNagtive)
    		{
    			numLeftVal = -numLeftVal;
    		}
    		
    		if(ret1 == 0 && ret2 == 0)
    		{
    			switch(sign)
    			{
    				case 1:
    					ret3 = GetResult(numLeftVal, numRightVal, '*', &result);
    					break;
    				case 2:
    					ret3 = GetResult(numLeftVal, numRightVal, '/', &result);
    					break;
    				case 3:
    					ret3 = GetResult(numLeftVal, numRightVal, '+', &result);
    					break;
    				case 4:
    					ret3 = GetResult(numLeftVal, numRightVal, '-', &result);
    					break;
    				default:
    					ret3 = GetResult(numLeftVal, numRightVal, '+', &result);
    					break;
    			}
    			if(1 == ret3)
    			{
    				char tmp[128] = {0};
    				sprintf(tmp, "%lld", result);
    				if(strlen(tmp)<=0)
    				{
    					memcpy(tmp, "0", 2);
    				}
    				SetDlgItemText(hwndDlg, IDC_EXP, tmp);//设置结果
    				memset(gSign,0,3);
    			}	
    		}
    		
    		
    		
    	}
    	return 0;
    }
    
    //追加文本到编辑框
    int AppendText(HWND hwndDlg, int nID, const char* str)
    {
    	if(NULL == str)
    	{
    		return 0;
    	}
    
    	char buf[EXP_MAX_LEN+2] = {0};
    	int len1,len2;
    	GetDlgItemText(hwndDlg, nID, buf, sizeof(buf));
    	len1 = strlen(buf);
    	len2 = strlen(str);
    	if(len1+len2>=EXP_MAX_LEN)
    	{
    		return 0;
    	}
    	memcpy(&buf[len1], str, EXP_MAX_LEN-len1);
    	len1 = strlen(buf);
    	if(0 >= len1)
    	{
    		SetDlgItemText(hwndDlg, IDC_EXP, "0");
    		return 0;
    	}
    
    	int i = 0;
    	if(len1>1)
    	{	
    		for(i=0; i<len1; i++)//找到首个不为0的字符
    		{
    			if(buf[i] != '0')
    				break;
    		}
    	}
    	
    	if(0 == buf[i] || IsASign(&buf[i],1)>0 )//如果全是0，或者首个非0字符是运算符就可以保留一个0
    	{
    		if(buf[0] != '-' &&buf[i] != '-')//如果上一次计算结果不是负数
    		{
    			i--;
    		}		
    	}
    	SetDlgItemText(hwndDlg, IDC_EXP, &buf[i]);
    	return 0;
    }
    
    //退格--将编辑框文本内容最后一个字符删除
    int DeleteAChar(HWND hwndDlg, int nID)
    {
    	char buf[512] = {0};
    	UINT len = 0;
    	GetDlgItemText(hwndDlg, nID, buf, sizeof(buf));
    	len = strlen(buf);
    	if(len>512)
    	{
    		len = 511;
    		buf[512] = '\0';
    	}
    	if(len > 0)
    		buf[len-1] = '\0';
    
    	len = strlen(buf);
    	if(len == 0)//表达式不为空
    	{
    		buf[0] = '0';
    		buf[1] = '\0';
    	}
    	SetDlgItemText(hwndDlg, IDC_EXP, buf);
    	return 0;
    }
    
    //回调函数--接受并处理 点击(操作)窗口、控件 后产生的各种消息
    INT_PTR CALLBACK MyDialogProcess(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lParam)
    {
    	unsigned short id = 0;
    	
    	switch(uMsg)
    	{
    		case WM_INITDIALOG://初始化对话框的时候，将编辑框内容设置为0
    			SetDlgItemText(hwndDlg, IDC_EXP, "0");
    			//窗体句柄，窗体的顺序，窗体位置x,y;窗体大小宽高，参数可选项
    			SetWindowPos(hwndDlg,HWND_TOPMOST,200,200,100,100,SWP_NOSIZE);//设置窗体位置，HWND_TOPMOST：窗体置顶，SWP_NOSIZE：忽略设置的窗体大小设置，即不改变窗体大小。
    			break;
    		case WM_COMMAND:
    			id =  LOWORD(wParam);
    			
    			switch(id)
    			{
    				case IDCANCEL:
    					EndDialog(hwndDlg, IDCANCEL);//退出，关闭对话框
    					break;
    				case IDC_BUTTON9:
    					AppendText(hwndDlg, IDC_EXP, "9");
    					break;
    				case IDC_BUTTON8:
    					AppendText(hwndDlg, IDC_EXP, "8");
    					break;
    				case IDC_BUTTON7:
    					AppendText(hwndDlg, IDC_EXP, "7");
    					break;
    				case IDC_BUTTON6:
    					AppendText(hwndDlg, IDC_EXP, "6");
    					break;
    				case IDC_BUTTON5:
    					AppendText(hwndDlg, IDC_EXP, "5");
    					break;
    				case IDC_BUTTON4:
    					AppendText(hwndDlg, IDC_EXP, "4");
    					break;
    				case IDC_BUTTON3:
    					AppendText(hwndDlg, IDC_EXP, "3");
    					break;
    				case IDC_BUTTON2:
    					AppendText(hwndDlg, IDC_EXP, "2");
    					break;
    				case IDC_BUTTON1:
    					AppendText(hwndDlg, IDC_EXP, "1");
    					break;
    				case IDC_BUTTON0:
    					AppendText(hwndDlg, IDC_EXP, "0");
    					break;
    				case IDC_BUTTONPlus:
    					GetExpResult(hwndDlg, IDC_EXP);	
    					if(1 != LastCharIsSign(hwndDlg,IDC_EXP))//前面不是运算符时，才能添加（两个运算符不能在一块）
    					{
    						AppendText(hwndDlg, IDC_EXP, "+");
    						memcpy(gSign,"+",2);
    					}
    					break;
    				case IDC_BUTTONSub:
    					GetExpResult(hwndDlg, IDC_EXP);	
    					if(1 != LastCharIsSign(hwndDlg,IDC_EXP))
    					{
    						AppendText(hwndDlg, IDC_EXP, "-");
    						memcpy(gSign,"-",2);
    					}
    					
    					break;
    				case IDC_BUTTONMul:
    					GetExpResult(hwndDlg, IDC_EXP);	
    					if(1 != LastCharIsSign(hwndDlg,IDC_EXP))
    					{
    						AppendText(hwndDlg, IDC_EXP, "×");
    						memcpy(gSign,"×",2);
    					}
    					break;
    				case IDC_BUTTONDiv:
    					GetExpResult(hwndDlg, IDC_EXP);	
    					if(1 != LastCharIsSign(hwndDlg,IDC_EXP))
    					{
    						AppendText(hwndDlg, IDC_EXP, "÷");
    						memcpy(gSign,"÷",2);
    					}
    					break;
    				case IDC_BUTTONClear:
    					SetDlgItemText(hwndDlg, IDC_EXP, "0");
    					memset(gSign,0,3);
    					break;
    				case IDC_BUTTONDel:
    					DeleteAChar(hwndDlg, IDC_EXP);
    					break;
    				case IDC_BUTTONEqual://计算结果
    					GetExpResult(hwndDlg, IDC_EXP);						
    					break;
    				case IDC_MenuAbout:
    					//参数：父窗口 内容 标题 按钮类型及个数
    					MessageBox(NULL, "这是一个简单的计算器!!!", "提示", MB_ICONINFORMATION|MB_OKCANCEL);//消息框,返回的是按钮编号
    					break;
    			}
    
    			break;
    		
    	}
    	return 0;
    }
    
    //程序主入口
    int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrev, LPSTR lpCmd, int nCmdShow)
    {	
    	//添加图标，直接添加即可
    	
    	//参数：资源 对话框ID 父窗口 回调函数
    	DialogBox(hInstance,(LPSTR)IDD_DIALOG1, NULL, MyDialogProcess);//弹出一个对话框
    
    	return 0;
    }

五、总结

5.1  一些函数的简单介绍

hwnd:窗口句柄
    nID：控件ID
    int GetDlgItemInt(hwnd, nID, NULL, TRUE);获取编辑框内容为一个数字
    SetDlgItemInt(hwnd, nID, aNumber, TRUE);设置编辑框内容为一个数字，aNumber：要设置的数字
    GetDlgItemText(hwnd, nID, str, sizeof(str));获取编辑框文本内容,（放到str中，通常str是字符数组）
    SetDlgItemText(hwnd, nID, str);设置编辑框文本内容，str：要设置的文本
    SetWindowText(hwnd, str);设置窗口标题，str：要设置的标题
    SetWindowPos(hwnd,HWND_TOPMOST,X,Y,cx,cy,uFlags);设置窗体位置，HWND_TOPMOST：窗口显示在最前面

以上API函数相关细节请参考：WinUser.h

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmZlaWJ1eWk_size_16_color_FFFFFF_t_70 1][]

5.2 添加资源

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmZlaWJ1eWk_size_16_color_FFFFFF_t_70 2][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmZlaWJ1eWk_size_16_color_FFFFFF_t_70 3][]

[20190920182033285.gif]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/11/d49654a134ae4fc4913d171b2d5cb3f1.gif
[2019092018205595.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/11/8db296719ea5423d9f622113b9141831.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmZlaWJ1eWk_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20190901152655500.PNG?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmZlaWJ1eWk=,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmZlaWJ1eWk_size_16_color_FFFFFF_t_70 1]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/11/027a310027834166990dd819d5b1eef9.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmZlaWJ1eWk_size_16_color_FFFFFF_t_70 2]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/11/99eb41fa6fea4b83b72d60b10311a9eb.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmZlaWJ1eWk_size_16_color_FFFFFF_t_70 3]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/11/ccbd55bf8f544ab891f7d46a1bc38daf.png