public void ProcParentheses(int index, OperatorType op)
{
if (op == OperatorType.L_Parentheses) //左括号
{
needOp = false;
needParentheses = false;
stackOp.Push(op);
}
else if (op == OperatorType.R_Parentheses) //右括号
{
bool find = false;
//如果是函数，则此处为函数的参数个数
//通过统计逗号的个数得出参数的个数
int funcParam = 1;
while (stackOp.Count > 0)
{
if (stackOp.Peek() != OperatorType.L_Parentheses)
{
OperatorType opPop = stackOp.Pop();
if (opPop == OperatorType.Comma)
{
funcParam++;
}
else
{
rePoland.Add(new ExpressionToken(TokenType.Operator, opPop));
}
}
else
{
stackOp.Pop();
find = true;
break;
}
}
if (!find)
{
throw new ExpressionException("括号不匹配.(缺少左括号)", 1003);
}
//如果再前一个是函数，也要加到 rePoland 中
if (stackOp.Count > 0)
{
OperatorType opPrev = stackOp.Peek();
if (IsFunc(opPrev))
{
//先判断函数的参数个数是否正确
FunctionBase func = FuncFactory.GetFunc((int)opPrev);
if (func.ParamCount != funcParam)
{
throw new ExpressionException("函数(" + func.Name + ")参数个数不正确\n"
+ "应为" + func.ParamCount + "个,"
+ "实为" + funcParam + "个");
}
rePoland.Add(new ExpressionToken(TokenType.Operator, stackOp.Pop()));
}
}
}
}
/// <summary>
/// 计算二元表达式的值
/// </summary>
public object CalcOperator(OperatorType op, decimal?[] data)
{
if (IsBaseOperator(op))
{
decimal?d1 = data[0];
decimal?d2 = data[1];
if (d1 == null || d2 == null)
{
return(DBNull.Value);
}
switch (op)
{
case OperatorType.Plus:
return(d1 + d2);
case OperatorType.Subtract:
return(d1 - d2);
case OperatorType.MultiPly:
return(d1 * d2);
case OperatorType.Divide:
if (d2 == 0)
{
throw new DivideByZeroException();
}
return(d1 / d2);
case OperatorType.Power: //幂运算
return(Math.Pow((double)d1, (double)d2));
}
}
else if (IsFunc(op))
{
FunctionBase func = FuncFactory.GetFunc((int)op);
if (func == null)
{
throw new ExpressionException("不可识别的函数名.");
}
else
{
func.Data = data;
try
{
return(func.Calc());
}
catch (Exception ex)
{
throw new ExpressionException("函数计算出错:" + ex.Message, 9000);
}
}
}
return(0);
}
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);
}
}