private object CalcInner()
{
int index = 0;
//存放常数表
List <decimal?> digit = new List <decimal?>();
//备份表达式
List <ExpressionToken> polandCalc = new List <ExpressionToken>(rePoland.Count);
for (int i = 0; i < rePoland.Count; i++)
{
polandCalc.Add(rePoland[i]);
}
while (index < polandCalc.Count)
{
if (polandCalc.Count == 1 && polandCalc[0].Type == TokenType.Numeric)
{
break;
}
ExpressionToken token = polandCalc[index];
switch (token.Type)
{
case TokenType.Numeric:
if (polandCalc[index].Data == DBNull.Value)
{
digit.Add(null);
}
else
{
digit.Add(Convert.ToDecimal(polandCalc[index].Data));
}
index++;
break;
//case TokenType.Variant:
// //将变量替换为常量
// polandCalc[index].Data = GetVariantValue(token);
// polandCalc[index].Type = TokenType.Numeric;
// break;
case TokenType.Operator:
int paramCount = 2; //一般是二元式，需要二个参数
//函数
if (IsFunc((OperatorType)token.Data))
{
FunctionBase func = FuncFactory.GetFunc((int)(OperatorType)token.Data);
if (func == null)
{
throw new ExpressionException("不可识别的函数名.");
}
paramCount = func.ParamCount;
}
//计算前面两个数的值
if (digit.Count < paramCount)
{
throw new ExpressionException("缺少操作数", 1002);
}
//传入参数
decimal?[] data = new decimal?[paramCount];
for (int i = 0; i < paramCount; i++)
{
data[i] = digit[index - paramCount + i];
}
polandCalc[index - paramCount].Data = CalcOperator((OperatorType)token.Data, data);
//将参数从 repoland 中移除
for (int i = 0; i < paramCount; i++)
{
polandCalc.RemoveAt(index - i);
digit.RemoveAt(index - i - 1);
}
index -= paramCount;
break;
default:
break;
}
}
if (polandCalc.Count == 1)
{
switch (polandCalc[0].Type)
{
case TokenType.Numeric:
return(polandCalc[0].Data);
default:
throw new ExpressionException("缺少操作数", 1002);
}
}
else
{
throw new ExpressionException("缺少操作符或操作数", 1002);
}
}