public override string Equal(string strOperator = "+", bool isEqualSign = false)
{
Reset = false;
if (OperatorClicked && !isEqualSign)
{
return(total);
}
OperatorClicked = true;
if (total == null)
{
lastOperator = strOperator;
total = sOperatorNum;
sOperatorNum = null;
//tbDisplayScreen.Text = "0";
Button_Clear = true;
return(total);
}
if (lastOperator == "" || sOperatorNum == "")
{
return(total);
}
if (sOperatorNum == "0" && lastOperator == "/")
{
Button_Clear = true;
Reset = true;
total = null;
return("除数不能为零");
}
calculate = operationFactory.createOperate(lastOperator);
calculate.NumberA = Convert.ToDouble(total);
calculate.NumberB = Convert.ToDouble(sOperatorNum);
total = calculate.GetResult().ToString();
if (isEqualSign)
{
Reset = true;
}
lastOperator = strOperator;
Button_BackSpace = false;
Button_Clear = true;
return(total);
}