Question

i am programatically adding Webcontrols in to a User Control i am also adding a javascript event passing the controlID as a parameter but the clientID is the one i assigned a it does not contain the one that asp.net generates

   var txt = new TextBox();    txt.ID = 'MyID'+Number;     chkBox.Attributes.Add('onClick', 'EnableTxtBox('' +txt.ClientID + '');'); 

i can workAround this by adding the parent control ID

   chkBox.Attributes.Add('onClick', 'EnableTxtBox('' + this.ClientID+'_'+txt.ClientID + '');'); 

On which Page life cycle are the Client IDs generated?

Answer 1

You need to add the control to the control hierarchy before you add the attribute.

   var txt = new TextBox();    txt.ID = 'MyID'+Number;    Controls.Add ( txt );    chkBox.Attributes.Add('onClick', 'EnableTxtBox('' +txt.ClientID + '');'); 

ControlCollection is no ordinary collection; it notifies the owner control when controls are added, and the control can take appropriate actions.