Creating Dynamic Server Controls and Associate Events.

Create an Array of Server controls dynamically and capture their events.

Adding Controls Dynamically
Controls can belong to a collection of that particular control. This collection is stored as an array.
CheckBox[] cbxYesArray = new CheckBox[3];
cbxYesArray[0] = new CheckBox();
cbxYesArray[0].Text = "YES"; Because arrays must be initialized, the number of controls must be determined before use (typically Page_Load) so that the array can be initialized to that number.   cbxYesArray = new CheckBox[iControlCount];
Controls that are added dynamically must belong to the page or a container control. Container controls
Include tables, panels, datagrids, etc.
tdControls.Controls.Add(cbxYesArray[i]); Once executed the ASP.NET page is removed from memory. Because of this the dynamic controls MUST BE recreated on each PostBack is the control is to be maintained on the page. Typically this occurs in the Page_Load event which will fire before other events.

  Adding the Events
When a Yes box is checked, change the Text to Green and reset the No box if it is checked. When a No box is checked, change the Text to Red and reset the Yes box if it is checked. If an entry is un-checked, reset the Text to black.

Two conditions must be met in order to capture the events:      1.   The control(s) must be re-initialized in the page before the event processing can occur. 
     2.   Because the control is not available during design, a separate event (method) must be created to handle to event(s) in question. That method is associated with the control when it is created.
           i.  VB uses the AddHandler statement
           ii  C# assigns the event with the EventHandler method
cbxYesArray[i].AutoPostBack = true; cbxYesArray[i].CheckedChanged += new EventHandler(CheckBoxClick);   By default, the CheckBox control does not automatically post the form to the server when it is clicked. To enable automatic posting, set the AutoPostBack property to true.
By using the ID property, you can store the position of the control in the array:

cbxYesArray[i].ID = "cbxY" + i;

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