DOM Document Object Model

The DOM is a document object that encapsulates the entire page into an object. A page is made up of a number of nodes, including elements, attributes, and text. There are three ways to get page elements.

First: getElementById, with the ID value to get all the properties of the entire label.

Second: getElementsByTagName, through the tag name value to get all the properties of the entire tag, it gets the elements will be in an array, you want to take the time, to use the method of the array to take.

Third: Getelementsbyclassname, through the class name to get all the properties of the entire tag, it gets the element will exist as an array, you have to take, to use the method of the array, but he shows in the array and the second kind of a bit different, it is a tag name with a class name as an array value , this compatibility is too strong, generally rarely used.

Event: A specific interaction moment that occurs in a document or browser window, with three elements: event source, event name, event handler. There are two types of registration events, inline, and in-line. On is a registered event.

The first type of inline:

The second type is inline:

To block A's jump we can use return false.

There are two APIs for getting page text: InnerText, InnerHTML.

1. Use innertext and innerHTML to get the content between page elements

2. The difference is that innertext only gets the text information, and innerHTML will also get the label between the tags, and it is output as is.

InnerText is not supported in the early Firefox browsers, the early Firefox browser only supports Textcontent, and the new version of Firefox supports both.

When the innertext is set, it is output as is,

Because innertext will escape the greater-than sign in the program.

And innerHTML will render the label inside as a normal HTML tag.

DOM Document Object Model