Add/Remove CSS class implementation code using jquery

One of the methods is to change the CSS class of page elements. In traditional JavaScript, we usually implement it by processing the classname feature of HTML Dom; jquery provides three methods to implement this function. Although they share the same idea with traditional methods, they save a lot of effort. Code . -"Jquery makes JavaScript code concise !"

1. addclass ()-add CSS class Copy codeThe Code is as follows: $ ("# target"). addclass ("newclass ");
// # Target indicates the ID of the element to add a style.
// Newclass refers to the CSS Class Name

2. removeclass ()-remove the CSS class Copy codeThe Code is as follows: $ ("# target"). removeclass ("oldclass ");
// # Target indicates the ID of the element to be removed from the CSS class.
// Oldclass refers to the CSS Class Name

3. toggleclass ()-Add or remove a CSS class: If the CSS class already exists, it will be removed. On the contrary, if the CSS class does not exist, it will be added.Copy codeThe Code is as follows: $ ("# target"). toggleclass ("newclass ")
// If the element whose ID is "target" has defined the CSS style, it will be removed;
// Conversely, the CSS class "newclass" will be assigned to this ID.

4. hasclass ("classname")-determine whether CSS exists

In practical use, we often define these CSS classes first, and then use JavaScript event triggers (such as clicking a link) to change the page element style. In addition, jquery provides a hasclass ("classname") method to determine whether an element has been assigned to a CSS class.