private static void GetValue2(ExpressionOperatorItem item, Stack<ExpressionOperatorItem> operatorStack, List<ExpressionItem> result)
{
if (!operatorStack.IsEmpty())
{
do
{
ExpressionOperatorItem tmpItem = operatorStack.Pop();
if (item.Value.Priority > tmpItem.Value.Priority)
//如果栈顶元素的优先级小于读取到的操作符
{
operatorStack.Push(tmpItem); //将栈顶元素放回堆栈
operatorStack.Push(item); //将读取到的操作符放回堆栈
break;
}
else //如果栈顶元素的优先级比较高或者两者相等时
{
result.Add(tmpItem); //将栈顶元素弹出，放入B中
if (operatorStack.IsEmpty())
{
operatorStack.Push(item); //将读取到的操作符压入堆栈中
break;
}
}
} while (!operatorStack.IsEmpty());
}
else //如果堆栈为空，就把操作符放入堆栈中
{
operatorStack.Push(item);
}
}
private static void GetValue(ExpressionOperatorItem item, Stack<ExpressionOperatorItem> operatorStack, List<ExpressionItem> result)
{
if (item.Value.ToString() == OperatorConst.LeftBracket)
{
//如果是'('，将它放入堆栈中
operatorStack.Push(item);
}
else if (item.Value.ToString() == OperatorConst.RightBracket) //如果是')'
{
while (!operatorStack.IsEmpty()) //不停地弹出堆栈中的内容，直到遇到'('
{
var tmpItem = operatorStack.Pop();
if (tmpItem.Value.ToString() == OperatorConst.LeftBracket)
{
break;
}
else
{
result.Add(tmpItem); //将堆栈中弹出的内容放入B中
}
}
}
else //既不是'('，也不是')'，是其它操作符，比如+, -, *, /之类的
{
GetValue2(item, operatorStack, result);
}
}
