How to use getElementById in JavaScript

getElementById is a method that returns an element with a specified id value as an Element object. You can use getElementById to obtain the specified ID from the HTML tag to process certain content. Let's take a closer look at how to use getElementById.

Usage of getElementById

The way to get the element using getElementById is as follows

document.getElementById(id)

Set the id you want The id element obtained in HTML. Since the same id cannot be used multiple times in HTML, it must be a unique id value.

If there are multiple ids in the HTML, only the first matching id element is returned. If the specified id does not exist, null is returned.

Let’s look atspecific examples

Display characters

The code is as follows

The running results are as follows

Display the connection text

The running results are as follows

Display calculation results

The running results are as follows

##Finally, Since there are many uses of getElementById in DOM (Document Object Model), we need to master it as much as possible.

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