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JavaScript Interactive Web Pages with JavaScript Selecting Elements and Adding Events with JavaScript Perform: Selecting Elements

david marjanac
david marjanac
4,851 Points

why you put in var=button array [0]

dont know why ther is [0] in var addButton=document.getElementByTagName("button")[0];

1 Answer

Robert Karlsson
Robert Karlsson
8,021 Points

From the getElementsByTagName-method you get a nodelist back with all matching elements. The [0] at the end gives you the first element in the list.

An example of a method that doesn't need the [0] at the end is the getElementById, since it only returns a single element, instead of a list of elements.