Document.all means all the elements of the document, that is, it contains all the elements of the current web page. It is the properties of the elements in the form of an array, so we can use the document.all ["element name"]. Property name = "Attribute Value" to dynamically change the properties of the element. With this statement, you can make a lot of dynamic webpage effects, such as dynamically transform pictures, dynamically change the background of text, dynamically change the background of the web page, dynamically change the size of the picture, dynamically change the size of the text, and so on. You can dynamically control all web elements.
