This is a BlogPosts control which has built-in implementation for comments. The main control that is used for the comments is RadEditor control. You can use IComment objects to create a new comment for each post.
IComment comment =
Then you have to create a repeater that shows all content items. You also have to override InitializeConrols and set the datasource of the Repeater when a given post is opened and also set initial values and subscribing for events of layout controls. Here you can use GetComments method of ContentManager
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