Roles and differences between disabled and readonly _ HTML/Xhtml _ webpage Creation

Readonly is to lock this control, where disabled and readonly are the same, the user can lock this control and cannot change its value, but the disabled is more thorough 1: readonly is used to lock the control and cannot be modified on the interface (but it can be modified through javascript ).

2: If disabled and readonly are the same, the user can lock this control and cannot change its value. However, disabled is more thorough, so that you cannot use it at all, this includes changing the background color (do not believe it, you modify an input text box that is disabled, and you find that you are in vain). If it is a checkbox, you cannot select it.

3: All controls have the disabled attribute, but not necessarily the readonly attribute. For example, select drop-down box