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Ken Hibino
17,009 PointsClass or Id?
I have a very rudimentary question. When you are building a base layout for a webpage, why do people usually give a class rather than an id, when you only use that class one time. (For example, class="main-logo", instead of id="main-logo"). Isn't it more efficient to select ids than classes. Could someone please answer this very basic question?
2 Answers
Lin Lu
29,171 PointsClass selector in CSS is used to select multiple elements in your HTML, they share the same class attribute. However, ID is unique, meaning you can select only one element at a time using an ID selector.
Ken Hibino
17,009 PointsThanks guys! It helped me clarify the difference between the two :)
Ken Hibino
17,009 PointsKen Hibino
17,009 PointsSo you use class="main-logo" because you want to use it in other part of the page?
Ayoub AIT IKEN
12,314 PointsAyoub AIT IKEN
12,314 Pointsor you may want to use it in other pages ;) !
Lin Lu
29,171 PointsLin Lu
29,171 PointsYes it is possible to use the same class more than once in the same page. Another difference between class and ID is that an element can have several classes, but only one ID. For example:
<button class="btn btn-default" id="btn">Button</button>In your case, you might want to apply other classes than "main-logo" to the same element.