Check the sample..
protected void Page_Load(object sender, EventArgs e)
{
String[] myArray = { "1", "4", "5", "6", "7" };
Session["arr"] = myArray;
}
protected void SendButton_Click(object sender, EventArgs e)
{
String[] test = (String[])Session["arr"];
}
From your code as you want to use the array in session in
CheckButton_Click
event without happening of this event if you click on
SendButton
the session will be null.