private List <Element> construct(string code)
{
List <string> toks = CompilerCore.AdcancedSplit(code.Trim(' ', '\t', '\r'));
//整理代码,中缀运算符改后缀
List <Element> restok = new List <Element>();
Stack <string> elestack = new Stack <string>();
foreach (string data in toks)
{
if (data.Length == 0)
{
continue;
}
Element tmpEle;
if (data.Contains("(") && data.Contains(")")) //是函数
{
tmpEle = new FunctionElement(data, Element.Function);
restok.Add(tmpEle);
}
else if (data.Contains("[") && data.Contains("]")) //是数组
{
tmpEle = new Element(data, Element.Array);
restok.Add(tmpEle);
}
else if (data[0] >= '0' && data[0] <= '9') //是数字
{
tmpEle = new Element(data, Element.Number);
restok.Add(tmpEle);
}
else if (data[0] >= 'a' && data[0] <= 'z' || data[0] >= 'A' && data[0] <= 'Z') //是一个变量
{
tmpEle = new Element(data, Element.Variable);
restok.Add(tmpEle);
}
else if (data[0] == '"') //是字符串
{
tmpEle = new Element(data, Element.String);
restok.Add(tmpEle);
}
else //是符号
{
if (elestack.Count == 0 || data == "(")
{
elestack.Push(data);
}
else
{
if (data == ")")
{
while (elestack.Peek() != "(" && elestack.Count > 0)
{
restok.Add(new Element(elestack.Pop(), Element.Symbol));
}
if (elestack.Count == 0)
{
throw new SyntaxErrorException("syntax error,the number of '(' and ')' don't match!");
}
elestack.Pop();
}
else
{
if (CompilerCore.operator_priority[data] >= CompilerCore.operator_priority[elestack.Peek()])
{
elestack.Push(data);
}
else
{
if (elestack.Peek() == "(")
{
elestack.Push(data);
}
else
{
while (CompilerCore.operator_priority[data] < CompilerCore.operator_priority[elestack.Peek()] && elestack.Count > 0)
{
if (elestack.Peek() == "(")
{
elestack.Pop();
break;
}
restok.Add(new Element(elestack.Pop(), Element.Symbol));
}
elestack.Push(data);
}
}
}
}
}
}
//将栈中的剩余运算符按序插入到表达式后面
while (elestack.Count > 0)
{
if (elestack.Peek() == "(")
{
elestack.Pop();
continue;
}
restok.Add(new Element(elestack.Pop(), Element.Symbol));
}
return(restok);
}