Conditional object operator overload & (and), | (OR)

I have discussed data components with my friends (hfsoft. data) condition object, which makes it inconvenient for the same condition object to construct complex conditions, and is difficult to maintain. for example, (orderid> 10600) and Order <10700) or (orderid> 10800 and orderid <10900), constructing conditional objects is not intuitive and difficult to maintain in the future. this complex SQL condition is often encountered during development! In this case, the condition object will Program Worse! Later, he made a comment on whether the condition object can be added with Operator Overloading and sent to the related technical application website.
After reading the information, I knocked on my head. I didn't even think of it (I didn't have a good foundation !), Conditional objects are much more convenient and concise to use after being overloaded with operators. the preceding condition example overload the query object expression :( (exp1 & exp2) | (exp3 & exp4 )). the expected results are unexpected. The operator overload is really an error-free function. Unfortunately, I have never thought of it before!
(Orderid> 10600) and Order <10700) or (orderid> 10800 and orderid <10900) or employeeid = 1
Query by condition object Code As follows:
Using (hfsoft. Data. idatasession session = hfsoft. Data. mappingcontainer. configcontainer. opensession ())
{
Expression exp1 = expressionfactory. RT ("orderid", 10600) & expressionfactory. Le ("orderid", 10700 );
Expression exp2 = expressionfactory. RT ("orderid", 10800) & expressionfactory. Le ("orderid", 10900 );
Session. open ();
System. Collections. ilist list = session. List (typeof (northwind. entitys. Orders), (exp1 | exp2) | expressionfactory. eq ("employeeid", 1 ));
This. Maid = List;
}
Case code