/// <summary>
/// 解析用户输入的条件表达式
/// </summary>
/// <param name="parseCondition">条件表达式</param>
/// <returns>解析结果</returns>
public bool CacluateCondition(string parseCondition)
{
if (string.IsNullOrEmpty(parseCondition))
{
return(true);
}
ParseExpression pe = new ParseExpression();
pe.UserFunctions = (IExpParsing)this;
pe.ChangeExpression(parseCondition);
object condValue = pe.Value();
return((bool)condValue);
}
/// <summary>
/// 解析用户输入的条件表达式
/// </summary>
/// <param name="parseCondition">条件表达式</param>
/// <returns>解析结果</returns>
public decimal CacluateExpression(string Expression)
{
if (string.IsNullOrEmpty(Expression))
{
throw new Exception("Expression is null");
}
ParseExpression pe = new ParseExpression();
pe.UserFunctions = (IExpParsing)this;
pe.ChangeExpression(Expression);
object condValue = pe.Value();
decimal result = decimal.MinValue;
decimal.TryParse(condValue.ToString(), out result);
return(result);
}
private object CalculateFunction(string strFuncName, ParamObject[] arrParams, ParseExpression parseObj)
{
object oValue = null;
try
{
switch (strFuncName.ToLower())
{
case "now":
oValue = DateTime.Now;
break;
case "today":
oValue = DateTime.Today;
break;
case "dateinterval.day":
oValue = "d";
break;
case "dateinterval.hour":
oValue = "h";
break;
case "dateinterval.minute":
oValue = "n";
break;
case "dateinterval.second":
oValue = "s";
break;
case "dateinterval.millisecond":
oValue = "ms";
break;
case "datediff":
oValue = DoDateDiff(arrParams);
break;
case "mindate":
oValue = DateTime.MinValue;
break;
case "maxdate":
oValue = DateTime.MaxValue;
break;
default:
{
if (UserFunctions != null)
{
oValue = UserFunctions.CalculateUserFunction(strFuncName, arrParams, this);
}
break;
}
}
return(oValue);
}
catch (System.Exception ex)
{
throw new ApplicationException(string.Format("函数{0}错误，{1}", strFuncName, ex.Message));
}
}
/// <summary>
/// 计算表达式
/// </summary>
/// <param name="strFuncName">函数名</param>
/// <param name="paramObject">参数</param>
/// <param name="parseObj">ParseExpression变量</param>
/// <returns>计算结果</returns>
public object CalculateExpression(string strFuncName, ParamObject[] paramObject, ParseExpression parseObj)
{
object returnValue = null;
switch (strFuncName.ToLower())
{
case "getvalue":
returnValue = GetValueFunction((string)paramObject[0].Value); //属性名称
break;
case "getstringvalue":
returnValue = GetStringValueFunction((string)paramObject[0].Value); //属性名称
break;
case "istrue":
returnValue = IsTrue((string)paramObject[0].Value); //属性名称
break;
case "getdatevalue":
returnValue = GetDateValueFunction((string)paramObject[0].Value); //属性名称
break;
}
return(returnValue);
}
/// <summary>
/// 实现IExpParsing接口CalculateUserFunction函数，目前未用
/// </summary>
/// <param name="strFuncName" >函数名称</param>
/// <param name="arrParams" >参数数组</param>
/// <param name="parseObj" >表达式对象</param>
/// <returns>解析获得的结果对象</returns>
public object CalculateUserFunction(string strFuncName, ParamObject[] arrParams, ParseExpression parseObj)
{
return(CalculateExpression(strFuncName, arrParams, parseObj));
}