private IExpression GetByUnit(FilterUnitBase unit, Expression parameterExpression)
{
if (unit is ParameterFilterUnit parameter)
{
return(new PropertyExpression(parameterExpression, parameter.PropertyName));
}
else
if (unit is ConstFilterUnit constant)
{
return(new ConstExpression(constant.Value, constant.Value.GetType()));
}
else if (unit is BinaryFilterUnit complex)
{
var expr1 =
GetByUnit(complex.Unit1, parameterExpression);
var expr2 =
GetByUnit(complex.Unit2, parameterExpression);
return(new CustomBinaryExpression(expr1, expr2, complex.OperatorType));
}
else if (unit is GroupFilterUnit group)
{
List <IExpression> exps =
new List <IExpression>();
foreach (var filterUnitBase in @group.Units)
{
exps.Add(GetByUnit(filterUnitBase, parameterExpression));
}
return(new CustomGroupExpression(exps.ToArray(), group.OperatorType));
}
else
{
throw new InvalidOperationException("");
}
}
public Search(FilterUnitBase filter)
{
_filter =
filter;
}