What do you do when you need a custom html element, like a button, listbox, radio button choice ?

1
As you can see, there is 4 choices of Layout in my example. If I used normal html element, I would replace the Web 2,Classic,Porte-Folio,Blog(Buttons) by a radio button.
2
In my example, there is "Social Network Link" Choice. The user can select as many social network as they wants. In Normal Html element, I would use a Listbox that give me the opportunity to select many option as I wants.
Here is my entity Framework Entities for this example
Layout
Id
LayoutName
SocialNetwork
Id
NetworkName
IconPath
WebSite
Id
LayoutID (FK With Layout) a website can Have only one layout chosen
WebSiteNetwork ( A Website can contain many network social link)
WebSiteID (FK With WebSite)
NetworkID (FK With Network)
based on your comment you can use the good old hidden input element like
attach a click event handler with the custom button
;
you can attach the hidden input to a form and on user selection of
Blogthe hidden input will hold the valueBlogon the server side you can look for the hidden field valueHTH