Question

In my main .aspx page I have a placeholder in which it get registered dynamically two types of user controls.

case "1":
   var control = (ControlType)LoadControl("~/PathToControl.ascx");
   control.Property = value;
   control.Initialize();
   placeholder.controls.add(control);
break;
case "2":
   var control1 = (ControlType)LoadControl("~/PathToControl1.ascx");
   control1.Property = value;
   control1.Initialize();
   placeholder.controls.add(control1);
break;

Each control has some user controls.

Now, in the main page I have a submit button and I want to get the values of each user coltrol from the above custom control.
I tried to get the controls of the placeholder but the placeholder after the postback is empty.

if(placeholder.Controls.count>0){
  var userControl = ((UserControlType)placeholder.Controls[0]);
  var controlName = userControl.FindControl("ControlName") as TextBox;
}

I tried also to build the custom controls on page_init but I still can’t get the user controls.

Does anyone know how can I achieve this?

SOLUTION

The dynamic user controls must be set in Init Event on each and every visit.

For more information http://msdn.microsoft.com/en-us/library/ms972976.aspx#viewstate_topic4

Answer 1

The controls must be registered in Init event

protected override void OnInit(EventArgs e) {
   case "1":
        var control = (ControlType)LoadControl("~/PathToControl.ascx");
        control.ID = "controlID";
        placeholder.controls.add(control);
  break;
  case "2":
      var control1 = (ControlType)LoadControl("~/PathToControl1.ascx");
      control.ID = "controlID_1";
      placeholder.controls.add(control1);
   break;
base.OnInit(e);
}

set whatever properties you want after the Init

case "1":
  var control = (ControlType)placeholder.findControl("ControlID");
  control.Property = value;
 control.Initialize();
break;
case "2":
 var control1 = (ControlType)placeholder.findControl("ControlID_1");
 control1.Property = value;
 control1.Initialize();
break;

After page’s post back

void LoadControls(){
   case "1":
    var control = (ControlType)placeholder.findControl("ControlID");
    var txtControl =  control.FindControl("controlName") as TextBox;
   break;
   case "2":
    var control1 = (ControlType)placeholder.findControl("ControlID_1");
    var txtControl_1 =  control1.FindControl("controlName") as TextBox;
   break;
 }