MFC开发——计算器制作

由于之前QT里面做过计算器，所以这次在MFC里面制作，除了函数库不同之外，逻辑都是照上一次的，而且最近特别忙，所以不会讲解太多，详情可以参考Qt开发——计算器制作

第一步：界面设计
建立基本对话框项目
设计界面如下

第二步，功能实现
头文件里面

private:
	CString m_str;	//显示内容
	int m_num1;		//储存数字1
	int m_num2;		//储存数字2
	int m_result;	//储存答案
	int m_opera;	//储存加减乘除，1代表+，2代表-，3代表*，4代表/
	bool m_opera_has_click;	//判断加减乘除是否已经按下
	bool m_num1_has_click;//判断num1已经按下

构造函数

	m_str="";
	m_num1=0;
	m_num2=0;
	m_result=0;
	m_opera_has_click=false;
	m_num1_has_click=false;

按钮功能实现

//////////////////////0~9按钮的实现/////////////////////////////


void CCalculatorDlg::OnButton1()  //按下1
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)//判断是否按下了运算符，没按下输入数字1，按下了则输入数字2
	{
		m_num1=m_num1*10+1;
		m_str+="1";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+1;
		m_str+="1";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}
}

void CCalculatorDlg::OnButton2() 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)
	{
		m_num1=m_num1*10+2;
		m_str+="2";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+2;
		m_str+="2";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}
}

void CCalculatorDlg::OnButton3() 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)//判断是否按下了运算符，没按下输入数字1，按下了则输入数字2
	{
		m_num1=m_num1*10+3;
		m_str+="3";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+3;
		m_str+="3";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}
}

void CCalculatorDlg::OnButton4() 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)//判断是否按下了运算符，没按下输入数字1，按下了则输入数字2
	{
		m_num1=m_num1*10+4;
		m_str+="4";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+4;
		m_str+="4";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}	
}

void CCalculatorDlg::OnButton5() 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)//判断是否按下了运算符，没按下输入数字1，按下了则输入数字2
	{
		m_num1=m_num1*10+5;
		m_str+="5";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+5;
		m_str+="5";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}		
}

void CCalculatorDlg::OnButton6() 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)//判断是否按下了运算符，没按下输入数字1，按下了则输入数字2
	{
		m_num1=m_num1*10+6;
		m_str+="6";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+6;
		m_str+="6";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}		
}

void CCalculatorDlg::OnButton7() 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)//判断是否按下了运算符，没按下输入数字1，按下了则输入数字2
	{
		m_num1=m_num1*10+7;
		m_str+="7";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+7;
		m_str+="7";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}		
}

void CCalculatorDlg::OnButton8() 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)//判断是否按下了运算符，没按下输入数字1，按下了则输入数字2
	{
		m_num1=m_num1*10+8;
		m_str+="8";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+8;
		m_str+="8";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}		
}

void CCalculatorDlg::OnButton9() 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)//判断是否按下了运算符，没按下输入数字1，按下了则输入数字2
	{
		m_num1=m_num1*10+9;
		m_str+="9";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+9;
		m_str+="9";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}		
}

void CCalculatorDlg::OnButton0() 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false)//判断是否按下了运算符，没按下输入数字1，按下了则输入数字2
	{
		m_num1=m_num1*10+0;
		m_str+="0";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_num1_has_click=true;
	}
	else
	{
		m_num2=m_num2*10+0;
		m_str+="0";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
	}	
}


/////////////////////////运算符的实现/////////////////////////////
void CCalculatorDlg::OnButtonAdd() //按下加号
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false&&m_num1_has_click==true)//判断是否按下了运算符与数字1，防止按下多次运算符与开始按下运算符
	{
		m_str+="+";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_opera_has_click=true;
		m_opera=1;
	}
	
}


void CCalculatorDlg::OnButtonDel() //按下减号 
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false&&m_num1_has_click==true)//判断是否按下了运算符与数字1，防止按下多次运算符与开始按下运算符
	{
		m_str+="-";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_opera_has_click=true;
		m_opera=2;
	}	
}

void CCalculatorDlg::OnButtonMul() //按下乘号
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false&&m_num1_has_click==true)//判断是否按下了运算符与数字1，防止按下多次运算符与开始按下运算符
	{
		m_str+="*";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_opera_has_click=true;
		m_opera=3;
	}
}


void CCalculatorDlg::OnButtonDiv() //按下除号
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==false&&m_num1_has_click==true)//判断是否按下了运算符与数字1，防止按下多次运算符与开始按下运算符
	{
		m_str+="/";
		GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
		m_opera_has_click=true;
		m_opera=4;
	}	
}

void CCalculatorDlg::OnButtonEqual() //按下等号
{
	// TODO: Add your control notification handler code here
	if(m_opera_has_click==true&&m_num1_has_click==true)//防止开始按下等号
	{
		switch(m_opera)
	{
	case 1:
		m_result=m_num1+m_num2;
		break;
	case 2:
		m_result=m_num1-m_num2;
		break;
	case 3:
		m_result=m_num1*m_num2;
		break;
	case 4:
		if(m_num2==0)//防止除数为0
		{
			MessageBox("错误：除数为0");

			//重置数据
			m_opera_has_click=false;
			m_num1_has_click=false;
			m_str="";
			m_num1=0;
			m_num2=0;
			m_result=0;
			GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
			break;
		}
		else
		{
				
		m_result=m_num1/m_num2;
		break;
		}
	}

	//计算显示结果
	m_str.Format("%d",m_result);
	GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);

	//重置数据
	m_opera_has_click=false;
	m_num1_has_click=false;
	m_str="";
	m_num1=0;
	m_num2=0;
	m_result=0;
	}
		
}


void CCalculatorDlg::OnButtonClear() //按下清除键
{
	// TODO: Add your control notification handler code here

	//重置数据
	m_str="";
	m_num1=0;
	m_num2=0;
	m_result=0;
	m_opera_has_click=false;
	m_num1_has_click=false;

	//清空屏幕
	GetDlgItem(IDC_EDIT1)->SetWindowText(m_str);
}

最后效果如图