What's the equivalence of an SQL WHERE in Lambda expressions?

Question

Hi,

Here's what I have:

decimal sum = _myDB.Products.Sum(p => p.Price).GetValueOrDefault();

I also have two dates: DateTime start, DateTime end
I want to retrieve the sum of all of the product prices between start and end, but I can't figure out how to incorporate the variables into the lambda equation.

How do you incorporate variables into a lambda equation to give it some specification?

Answer 1

Use Enumerable.Where

decimal sum = _myDB.Products
                   .Where(p => (p.Date >= start) && (p.Date <= end) )
                   .Sum(p => p.Price)
                   .GetValueOrDefault();

Answer 2

_myDB.Products
.Where(p => p.start >= "somevalue")
.Where(p => p.end <= "somevalue")
.Sum(p => p.Price).GetValueOrDefault();

Answer 3

 decimal sum = _myDB.Products
.Where(p => p.Start >= mystartDate && p.End <= myenddate)
.Sum(p => p.Price)

Pardon my syntax. But, I hope you get the idea.

EDIT: Corrected after Reed's suggestion.
Old code (incorrect)

 decimal sum = _myDB.Products
.Sum(p => p.Price)
.Where(p => p.Start >= mystartDate && p.End <= myenddate)