Question

Single and multiple lists

Consider the following lists:

List<Int32> appleIdentities = new List<int>(new[] { 1, 2, 3 }); List<Int32> chocolateIdentities = new List<int>(new[] { 2, 3, 4 }); List<Int32> icecreamIdentities = new List<int>(new[] { 11, 14, 15, 16 }); 

Using LINQ to SQL; is it possible to wite a statement which translates into:

SELECT     DesertsID,     DesertsName FROM     Deserts WHERE     Deserts.AppleIdentity IN (1, 2, 3) AND     Deserts.ChocolateIdentity IN (2, 3, 4) AND     Deserts.IcecreamIdentity IN (11, 14, 15m 16) 

If yes; how would the code look if I wanted to query my database of deserts against just the appleIdentities list?

Arrays

Consider the following arrays:

Int32[] appleIdentities = new[] {1, 2, 3, 4}; String[] chocolateNames = new[] {'Light', 'Dark'}; 

Using LINQ to SQL; is it possible to wite a statement which translates into:

SELECT     DesertsID,     DesertsName FROM     Deserts WHERE     Deserts.AppleIdentity IN (1, 2, 3) AND     Deserts.ChocolateName IN ('Light', 'Dark') 

If yes; how would the code look if I wanted to query my database of deserts against just the appleIdentities array?

List of objects

Consider the following:

public class Identities {     public Int32 appleIdentity { get; set; }     public String chokolateName { get; set; } }  List<Identities> identities = new List<Identities>(new[] {     new Identities { appleIdentity = 1, chokolateName = 'Light' },     new Identities { appleIdentity = 2, chokolateName = 'Dark' }, }); 

Using LINQ to SQL; is it possible to wite a statement which translates into:

SELECT     DesertsID,     DesertsName FROM     Deserts WHERE     Deserts.AppleIdentity IN (1, 2) AND     Deserts.ChocolateName IN ('Light', 'Dark') 

If yes; how would the code look if I wanted to query my database of deserts against just the appleIdentity-property on my list of Identities objects?

This is branch off of LINQ to SQL query against a list of entities

Answer 1

Sure – just use Contains – using Northwind as an example:

var qry = from cust in ctx.Customers           where custIds.Contains(cust.CustomerID)              && regions.Contains(cust.Region)           select cust; // or your custom projection