/// <summary>
/// 计算中缀表达式中的所有函数
/// </summary>
/// <param name="list"></param>
/// <returns></returns>
private LinkList calcFuns(LinkList list)
{
//遍历整个链表
ArrayList paramsList = new ArrayList(5);
LinkNode funNode = null, insertNode = null, nextTempNode = null;
for (LinkNode node = list.First; node != null; node = nextTempNode)
{
nextTempNode = node.Next; //node用于循环，而每次计算里都要将)删除，所有提前保存node的下一个结点的值
if (node.getWord().wordType == WordType.Leftp)
{
stack.Push(node);
}
else if (node.getWord().wordType == WordType.Rightp)
{
if (stack.Count < 1)
{
throw new Exception("括号不匹配，缺左括号");
}
else if (((LinkNode)stack.Peek()).Previous == null || ((LinkNode)stack.Peek()).Previous.getWord().wordType != WordType.FunName)
{
//括号只是一个表达式，而不属于一个函数
//条件是括号前面不是函数名，或括号前面没有元素
stack.Pop();
continue;
}
else
{
paramsList.Clear();
LinkNode start = (LinkNode)stack.Pop();
funNode = start.Previous;
insertNode = node.Next;
list.removeBetween(start, node);
LinkList innerList = new LinkList(start, node); //还包含括号
//第一种情况，括号里面没有任何参数
if (innerList.Count == 2) //判断括号里是否为空
{
//计算函数的值
double result = Function(funNode.getWord().valueString, paramsList);
list.remove(funNode);
list.insert(insertNode, new LinkNode(new Word(WordType.Number, result.ToString())));
continue;
}
else
{
innerList.remove(start); //删除括号
innerList.remove(node);
LinkNode comma = null;
comma = innerList.searchComma();
//第二种情况，括号里只有一个参数（参数表达式）
if (comma == null) //没有逗号
{
paramsList.Add(calculator.compute(innerList));
//根据参数计算函数的值
double result = Function(funNode.getWord().valueString, paramsList);
list.remove(funNode);
list.insert(insertNode, new LinkNode(new Word(WordType.Number, result.ToString())));
continue;
}
else /////第三种情况，括号里有多个参数表达式
{
while (comma != null)
{
LinkNode newStart = innerList.First;
innerList.removeBetween(newStart, comma);
LinkList tempList = new LinkList(newStart, comma);
if (tempList.Count < 2)
{
throw new Exception("逗号前面有问题");
}
tempList.remove(tempList.End); //删除逗号
paramsList.Add(calculator.compute(tempList));
comma = innerList.searchComma();
}
if (innerList.Count == 0)
{
throw new Exception("函数的逗号后面有问题");
}
else
{
paramsList.Add(calculator.compute(innerList));
//用多个参数计算函数
double result = Function(funNode.getWord().valueString, paramsList);
list.remove(funNode);
list.insert(insertNode, new LinkNode(new Word(WordType.Number, result.ToString())));
}
}
}
}
}
}
return(list);
}
/// <summary>
/// 计算中缀表达式的值
/// </summary>
/// <param name="list"></param>
/// <returns></returns>
public double compute(LinkList list)
{
this.list = list;
createSuffixExpression();
return(reckon());
}
