//清零
private void button111_Click(object sender, EventArgs e)
{
this.FirstNo = "";
this.SecondNo = "";
this.currentSign = CalculationSigns.Nothing;
数字显示框.Text = "";
运算表达试.Text = "";
}
//乘法
private void button_3_Click(object sender, EventArgs e)
{
currentSign = CalculationSigns.Multiply;
ClickDown();
}
//除法
private void button_4_Click(object sender, EventArgs e)
{
currentSign = CalculationSigns.Divide;
ClickDown();
}
//减法
private void button_2_Click(object sender, EventArgs e)
{
currentSign = CalculationSigns.Subtract;
ClickDown();
}
