Jorge Saldívar

Tag: web dev

  • In JavaScript, what is the difference between `.contains()` and `.includes()`?

    In JavaScript, .contains() and .includes() are used for different purposes:

    .contains(): This is a method of the Node interface in the Document Object Model (DOM). It’s used to check whether a node is a descendant of a given node, i.e., child, grandchild, etc.

    node.contains(otherNode)

    .includes(): This is a method of the Array and String prototypes in JavaScript. It’s used to determine whether an array includes a certain value among its entries or whether a string includes a certain substring.

    For arrays:

    array.includes(valueToFind, fromIndex)

    For strings:

    string.includes(searchString, position)

    So, the main difference is that .contains() is used with DOM nodes, while .includes() is used with arrays and strings.