Window.onload () and $ (document). Ready () method similarities and differences

Window.onload must wait until all the elements of the page that include the picture have been loaded before they can be executed.
$ (document). Ready () is executed when the DOM structure is drawn and does not have to wait for the load to complete.

Window.onload cannot write multiple at the same time, if there are multiple window.onload methods, only one
$ (document). Ready () can be written multiple at the same time and can be executed

Window.onload No simplified notation
$ (document). Ready (function () {}) can be simply written as $ (function () {});

It is important to note that because the event is registered within the (document). Ready () method, as long as the DOM is in place, the associated file for the element may not have been downloaded at this time. For example, the HTML download for the picture is complete and has been parsed into a DOM tree,

However, it is possible that the picture has not been loaded yet, so attributes such as the height and width of the case are not necessarily valid at this time. To solve this problem, you can use another method in Jquery about page loading---the load () method.

The Load () method binds a handler function in the OnLoad event of the element.

If the handler is bound to a Window object, it fires after all content (including Windows, frames, objects, images, and so on) is loaded, and if the handler is bound to the element, it is triggered after the element's contents have been loaded.
The Jquery code is as follows:
$ (window). Load (function () {
Writing code
}); equivalent to the following code in JavaScript
Window.onload = function () {
Writing code
}

Window.onload () and $ (document). Ready () method similarities and differences