Linq Where local counterclosing different results in VS watch

Question

I am trying to remove the first 3 elements in arrayusing the LinQ extension function Where.

Here is an example:

var array = new[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
var count = 3;
var deletedTest1 = 0;
var test1 = array.Where(x => ++deletedTest1 > count).ToList();
Console.WriteLine($"{{{String.Join(", ", test1)}}}");
var deletedTest2 = 0;
var test2 = array.Where(x => ++deletedTest2 > count).AsEnumerable();
Console.WriteLine($"{{{String.Join(", ", test2)}}}");
var deletedTest3 = 0;
var test3 = array.Where(x => ++deletedTest3 > count);
Console.WriteLine($"{{{String.Join(", ", test3)}}}");
var deletedTest4 = 0;
var test4 = array.Where(x => ++deletedTest4 > count).ToArray();
Console.WriteLine($"{{{String.Join(", ", test4)}}}");

It works great, and in each case I { 4, 5, 6, 7, 8, 9 }get a console .

But in watch in Visual Studio 2015 Update 3 in test2and in test3case I have the wrong result:

Can anyone explain why it's all right when I'm using .ToList()and .ToArray()and wrong in other cases?

This is mistake?

Answer 1

​​ . , , IEnumerable<T>, Where, , (, deletedTestX) .

. 1 4 ToList ToArray, 2 3 string.Join.

, , . , , . .

, :

var array = new[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
var count = 3;
var deletedTest1 = 0;
var test1 = array.Where(x => ++deletedTest1 > count).ToList();
Console.WriteLine("Test 1, deletedTest1={0}", deletedTest1);
Console.WriteLine($"{{{String.Join(", ", test1)}}}");
Console.WriteLine("Test 1, deletedTest1={0}", deletedTest1);
Console.WriteLine($"{{{String.Join(", ", test1)}}}");
var deletedTest2 = 0;
var test2 = array.Where(x => ++deletedTest2 > count).AsEnumerable();
Console.WriteLine("Test 2, deletedTest2={0}", deletedTest2);
Console.WriteLine($"{{{String.Join(", ", test2)}}}");
Console.WriteLine("Test 2, deletedTest2={0}", deletedTest2);
Console.WriteLine($"{{{String.Join(", ", test2)}}}");
var deletedTest3 = 0;
var test3 = array.Where(x => ++deletedTest3 > count);
Console.WriteLine("Test 3, deletedTest3={0}", deletedTest3);
Console.WriteLine($"{{{String.Join(", ", test3)}}}");
Console.WriteLine("Test 3, deletedTest3={0}", deletedTest3);
Console.WriteLine($"{{{String.Join(", ", test3)}}}");
var deletedTest4 = 0;
var test4 = array.Where(x => ++deletedTest4 > count).ToArray();
Console.WriteLine("Test 4, deletedTest4={0}", deletedTest4);
Console.WriteLine($"{{{String.Join(", ", test4)}}}");
Console.WriteLine("Test 4, deletedTest4={0}", deletedTest4);
Console.WriteLine($"{{{String.Join(", ", test4)}}}");