Aggregate two expressions in c# syntax

Question

How to aggregate two expressions in C#? For example:

public virtual List<T> List(Expression<Func<T, bool>> filters, bool includeHistory = false, params Expression<Func<T, object>>[] include)
{
    // HOW TO DO THIS?
    filters = includeHistory ? filters : filters.Add(e=>e.DeleteDate == null);    
    List<T> entities = _baseDao.List<T>(filters, sorting, include)                   
}

http://www.albahari.com/nutshell/predicatebuilder.aspx – SLaks Aug 04 '14 at 13:19 — SLaks, Aug 04 '14 at 13:19
What guarantees that T will have DeleteDate? – Mike Aug 04 '14 at 13:47 — Mike, Aug 04 '14 at 13:47
This is part of method of Generic class – Yuriy Mayorov Aug 04 '14 at 13:51 — Yuriy Mayorov, Aug 04 '14 at 13:51

score 0 · Answer 1 · answered Aug 04 '14 at 13:52

Joe Albahari (Author of C# 3.0 in a Nutshell and LINQPad) wrote a utility called PredicateBuilder which can be used to AND and OR functions together.

http://www.albahari.com/nutshell/predicatebuilder.aspx

While it works on functions it is open source so you can check it out and see how it works.

score 0 · Accepted Answer · edited May 23 '17 at 12:11

0

I found solution here

Very good extension method to Expression class

edited May 23 '17 at 12:11

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answered Aug 04 '14 at 13:53

Yuriy Mayorov

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Aggregate two expressions in c# syntax

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