Forms are fully supported in Bootstrap 4. Many of the components are primarily used to make the forms responsive, and can be used with any screen width.
Structure of a Form
Form elements automatically receive the correct formatting. The main class for controls is .form-control. Elements that have controllable horizontal extensions such as <input>, <textarea>, and <select> are set to a width of 100% of the parent container. The labels and inputs are grouped using .formgroup. They arrange themselves depending on the available width, either side-by-side or one above the other.
Simple Form Elements
Listing 5-1 gives an ...
