Is it safe to adopt idea of double-click on a radio button? [closed]

1. Should radio buttons always have a default?
2. Can radio button have more than 2 options?
3. How do I make a radio button non editable?
4. Can we use OnClick on radio button?

Should radio buttons always have a default?

Always Offer a Default Selection

This means enabling people to set a UI control back to its original state. In case of radio buttons this means that radio buttons should always have exactly one option pre-selected. Select the safest and most secure option (to prevent data loss).

Can radio button have more than 2 options?

Radio buttons are normally presented in radio groups (a collection of radio buttons describing a set of related options). Only one radio button in a group can be selected at the same time.

How do I make a radio button non editable?

Add("ReadOnly", "ReadOnly"); and this works.

Can we use OnClick on radio button?

Each RadioButton has been assigned a JavaScript OnClick event handler. Note: The RadioButtons must be set with exact same name attribute values in order to make them mutually exclusive. When the RadioButton is clicked, the ShowHideDiv JavaScript function is executed.