Little Web Hut

JavaScript & jQuery Video Tutorial

Part 2 - jQuery Selectors

JavaScript jQuery Tutorial part 2

The following code is from the Video.

HTML Code

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">

<head>
 <title>Demo</title>
 <meta http-equiv="content-type" content="text/html; charset=utf-8" />
</head>

<body>
  <input id="testbutton" type="button" value="Test" />
  
  <div>
    <p>This is the <strong>first</strong> line of text.</p>
    <p>This is the <strong>second</strong> line of text.</p>
  </div>
  
  <p>This is the <strong>third</strong> line of text.</p>
  <p>This is the <strong>fourth</strong> line of text.</p>

<script type="text/javascript" src="jquery-1.8.0.min.js"></script>
<script type="text/javascript" src="my_code.js"></script>
</body>

</html>

Element Selector

Select elements by tag name. Example: "div" - Selects all <div> elements.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("div").css("background-color","red");	
  });
});

Try it out.


Element Selector

Select elements by tag name. Example: "p" - Selects all <p> elements.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("p").css("background-color","red");	
  });
});

Try it out.


Multiple Selector

Select multiple elements by separating selectors with comas. Example: "div, strong, #testbutton" - Selects all <div> elements, <strong> elements, and the <input> element (the Test button) since its ID attribute is set to testbutton.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("div, strong, #testbutton").css("background-color","red");	
  });
});

Try it out.


All Selector

Select all elements by using an asterisk. Example: "*" - Selects all elements.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("*").css("background-color","red");	
  });
});

Try it out.


Child Selector

Selects a child element by using the following syntax. "parent > child". Example: "div > p" - Selects all <p> elements that are children of <div> elements.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("div > p").css("background-color","red");	
  });
});

Try it out.


First Child Selector

Selects first child elements by using the syntax :first-child. Example: "div > p:first-child" - Selects all <p> elements that are first children of <div> elements.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("div > p:first-child").css("background-color","red");	
  });
});

Try it out.


Last Child Selector

Selects last child elements by using the syntax :last-child. Example: "div > p:last-child" - Selects all <p> elements that are last children of <div> elements.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("div > p:last-child").css("background-color","red");	
  });
});

Try it out.


Descendant Selector

Selects a descendant element by using the following syntax. "ancestor descendant". Example: "div strong" - Selects all <strong> elements that are descendants of <div> elements.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("div strong").css("background-color","red");	
  });
});

Try it out.


Even Selector

Selects matched elements based on their position. Even positioned elements are selected using the following syntax. :even. Example: "p:even" - Selects the first and third <p> elements.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("p:even").css("background-color","red");	
  });
});

Try it out.


Odd Selector

Selects matched elements based on their position. Odd positioned elements are selected using the following syntax. :odd. Example: "p:odd" - Selects the second and fourth <p> elements.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("p:odd").css("background-color","red");	
  });
});

Try it out.


HTML Code

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">

<head>
 <title>Demo</title>
 <meta http-equiv="content-type" content="text/html; charset=utf-8" />
</head>

<body>
  <input id="testbutton" type="button" value="Test" />
  
  <div>
    <p class="multiple">This is the <strong>first</strong> line of text.</p>
    <p>This is the <strong class="multiple">second</strong> line of text.</p>
  </div>
  
  <p id="third">This is the <strong>third</strong> line of text.</p>
  <p>This is the <strong>fourth</strong> line of text.</p>

<script type="text/javascript" src="jquery-1.8.0.min.js"></script>
<script type="text/javascript" src="my_code.js"></script>
</body>

</html>

ID Selector

Selects the element whose ID attribute matches the specified name. The specified name is preceded by a #. Example: "#third" - Selects the element that has an ID attribute value of third.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("#third").css("background-color","red");	
  });
});

Try it out.


Class Selector

Select the elements whose class attribute matches the specified name. The specified name is preceded by a period. Example: ".multiple" - Selects all the element that have class attribute values of multiple.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $(".multiple").css("background-color","red");	
  });
});

Try it out.


Element with Class Selector

Select elements by the combination of tag name and class attribute. Specify the tag name, followed by a period, followed by a class name. Example: "strong.multiple" - Selects all <strong> elements that have class attribute values of multiple.

$(document).ready(function() {
  $("#testbutton").click(function() {
    $("strong.multiple").css("background-color","red");	
  });
});

Try it out.


Multiple Selector for the Click Event

The click event is using an ID selector and an element selector by specifying "#testbutton, strong" When either the Test Button, or a <strong> element is clicked, the background color of the <strong> element on the second line will turn red.

$(document).ready(function() {
  $("#testbutton, strong").click(function() {
    $("strong.multiple").css("background-color","red");	
  });
});

Try it out.


this Keyword Selector

The element that caused the click function to be executed is specified by using the keyword this, without quote marks. Clicking on the Test Button, or any of the <strong> elements, will cause the clicked element's background color to turn red.

$(document).ready(function() {
  $("#testbutton, strong").click(function() {
    $(this).css("background-color","red");	
  });
});

Try it out.