Dynamic where clause in LINQ - with column names available at runtime

Question

Disclaimer: I\'ve solved the problem using Expressions from System.Linq.Expressions, but I\'m still looking for a better/easier way.

Consider the following situation :

Answer 1

You can turn your where clauses on and off using some logic expressions.

//Turn on all where clauses
bool ignoreFirstName = false;
bool ignoreLastName = false;;
bool ignoreAddress = false;

//Decide which WHERE clauses we are going to turn off because of something.
if(something)
    ignoreFirstName = true; 

//Create the query
var queryCustomers = from c in db.Customers 
    where (ignoreFirstName || (c.ContactFirstName.Contains("BlackListed")))
    where (ignoreLastName || (c.ContactLastName.Contains("BlackListed")))
    where (ignoreAddress || (c.Address.Contains("BlackListed"))
    select j;  

If ignoreFirstName is true in the query then the condition on the other side of the or statement will be ignored.