jQuery Syntax
With jQuery you select (query) HTML elements and perform "actions" on them.
jQuery Syntax
The jQuery syntax is tailor-made for selecting HTML elements and performing some action on the element(s).
Basic syntax is: $(selector).action()
- A $ sign to define/access jQuery
- A (selector) to "query (or find)" HTML elements
- A jQuery action() to be performed on the element(s)
Examples:
$(this).hide() - hides the current element.
$("p").hide() - hides all <p> elements.
$(".test").hide() - hides all elements with class="test".
$("#test").hide() - hides the element with id="test".
jQuery Selector allow you to select and manipulate HTML elements.
jQuery Selector are used to find or select HTML elements based on their name,id,class,types,attributes
The Document Ready Event
The ready event's occurs when the dom(document object model) has been loaded because this event's occurs after the document is ready.
The ready method specifies what happens when a ready event occurs
You might have noticed that all jQuery methods in our examples, are inside a document ready event:
$(document).ready(function(){
// jQuery methods go here...
});
// jQuery methods go here...
});
This is to prevent any jQuery code from running before the document is finished loading (is ready).
It is good practice to wait for the document to be fully loaded and ready before working with it. This also allows you to have your JavaScript code before the body of your document, in the head section.
Here are some examples of actions that can fail if methods are run before the document is fully loaded:
Example
<script src="./jquery-3.2.1.js"> </script>
<script>
$(document).ready(function()
{
$("p").css("background-color","Pink");
$("h1").css("background-color","green");
$("#demo").css("background-color","Yellow");
});
<;/script>
<h1>Good Morning </h1>
<p>This is JQuery Demo Page</p>
<div> Have good day
See U Soon </div>