C# Linq where clause as a variable

Solution 1:

You need to assembly an Expression<Func<T, bool>> and pass it to the Where() extension method:

Expression<Func<T, bool>> whereClause = a => a.zip == 23456;
var x = frSomeList.Where(whereClause);

EDIT: If you're using LINQ to Objects, remove the word Expression to create an ordinary delegate.

Solution 2:

This:

var query = from something in someList where whereClause;

is shorthand for:

var query = someList.Where(something => whereClause);

Assuming someList is an IEnumerable<Address>, Where refers to the Enumerable.Where Extension Method. This method expects a Func<Address, bool> which you can define as follows:

Func<Address, bool> whereClause = address => address.Zip == 23456;
var query = someList.Where(whereClause);