Question

How to do this?

int[] mas={1,2,3,4,...,n}

public var method1(mas)
{
var d = from i in Object where i.number==mas[0] || i.number==mas[1] || i.number==mas[2]|| ... || i.number==mas[n] select i;
return d;
}

Answer 1

You will want to do something like this

var d = From i in Object
        From n in mas
        Where n == i.Number
        Select i;
return d;

Actually now that I think about that, that is going to return to you a list of i for every match.

You probably were looking for something more like

   //create a list for the items that match the criteria
    List<ObjectToGet> d = new List<ObjectToGet>;

    //Loop over each item in your Object
    foreach(ObjectToGet objectItem in Object){
        //If the item contains any match add it to the list
        if((From n in mas Where n == d.Number Select n).Any){
            d.Add(objectItem);
        }
    }

    return d;

There’s probably a way to write this in pure LINQ but this is conceptually what you are trying to do