 
public double? value1 = null ;//獲取運算符前的數(shù)值 
public double? value2 = null ;//獲取運算符前的數(shù)值 
public type caltype=type .none ;//獲取運算符 
private void btnvalue1_Click(object sender, EventArgs e) 
{ 
if (value1 == null) 
{ 
value1 = Convert.ToDouble(btnvalue1.Text); 
} 
else 
{ 
value2 = Convert.ToDouble(btnvalue1.Text); 
} 
this.txtvalue.Text = btnvalue1.Text; 
}“1”按鈕的單擊事件 

一共有十個這樣的數(shù)字鍵按鈕單擊事件
是不是覺得這樣寫很麻煩，于是就有了按鈕注冊事件。下面是我后面下的一段代碼：

復制代碼代碼如下:

 
public double? value1 = null ;//獲取運算符前的數(shù)值 
public double? value2 = null ;//獲取運算符后的數(shù)值 
public type caltype=type .none ;//獲取運算符 
private void Form1_Load(object sender, EventArgs e) 
{ 
btnvalue0.Click += new EventHandler(btnvalue_Click); 
btnvalue1.Click += new EventHandler(btnvalue_Click); 
btnvalue2.Click += new EventHandler(btnvalue_Click); 
btnvalue3.Click += new EventHandler(btnvalue_Click); 
btnvalue4.Click += new EventHandler(btnvalue_Click); 
btnvalue5.Click += new EventHandler(btnvalue_Click); 
btnvalue6.Click += new EventHandler(btnvalue_Click); 
btnvalue7.Click += new EventHandler(btnvalue_Click); 
btnvalue8.Click += new EventHandler(btnvalue_Click); 
btnvalue9.Click += new EventHandler(btnvalue_Click); 
//通過EventHandler將按鈕控件的Click事件 
綁定到 btnvalue_Click上面，從而動態(tài)注冊按鈕事件 
} 
private void btnvalue_Click(object sender, EventArgs e) 
{ 
Button btn =(Button)sender ; 
//實例化按鈕，從而獲取當前單擊按鈕的值 
if (value1 == null) 
{ 
value1 = Convert.ToDouble(btn.Text); 
} 
else 
{ 
value2 = Convert.ToDouble(btn.Text); 
} 
this.txtvalue.Text = btn.Text; 
} 