struct TestA
{
    public int val1;
}

class Program
{
    static void Main(string[] args)
    {
        TestA[] A = new TestA[10];

        // case 1
        A[0].val1 = 1;

        // case 2
        var t = A[0];
        t.val1 = 2;

        Console.WriteLine("val1 : {0}", A[0].val1);
    }
}