July 27, 2018
Chetan Velhal
HTML Attributes
attribute is used to define the
characteristics of an HTML element and is placed inside the element's opening
tag. All attributes are made up of two parts − a name and a value
The name is the property you want
to set. For example, the paragraph <p> element in the example carries an
attribute whose name is align, which you can use to indicate the alignment of
paragraph on the page.
The value is what you want the
value of the property to be set and always put within quotations. The below
example shows three possible values of align attribute: left, center and right.
Attribute names and attribute
values are case-insensitive. However, the World Wide Web Consortium (W3C)
recommends lowercase attributes/attribute values in their HTML 4
recommendation.
Example
<!DOCTYPE html>
<html>
<head>
<title>Align Attribute Example</title>
</head>
<body>
<p align = "left">This is
left aligned</p>
<p align = "center">This
is center aligned</p>
<p align = "right">This
is right aligned</p>
</body>
</html>
This will display the following
result −
Core Attributes
The four core attributes that can
be used on the majority of HTML elements (although not all) are −
- Id
- Title
- Class
- Style
The Id Attribute
The id attribute of an HTML tag
can be used to uniquely identify any element within an HTML page. There are two
primary reasons that you might want to use an id attribute on an element −
If an element carries an id
attribute as a unique identifier, it is possible to identify just that element
and its content.
If you have two elements of the
same name within a Web page (or style sheet), you can use the id attribute to
distinguish between elements that have the same name.
We will discuss style sheet in separate
tutorial. For now, let's use the id attribute to distinguish between two
paragraph elements as shown below.
Example
<p id =
"html">This para explains what is HTML</p>
<p id = "css">This
para explains what is Cascading Style Sheet</p>
This will produce the following result −
The title Attribute
The title attribute gives a
suggested title for the element. They syntax for the title attribute is similar
as explained for id attribute −
The behavior of this attribute
will depend upon the element that carries it, although it is often displayed as
a tooltip when cursor comes over the element or while the element is loading.
Example
<!DOCTYPE html>
<html>
<head>
<title>The title Attribute
Example</title>
</head>
<body>
<h3 title = "Hello
HTML!">Titled Heading Tag Example</h3>
</body>
</html>
This will produce the following
result −
Now try to bring your cursor over
"Titled Heading Tag Example" and you will see that whatever title you
used in your code is coming out as a tooltip of the cursor.
The class Attribute
The class attribute is used to
associate an element with a style sheet, and specifies the class of element.
You will learn more about the use of the class attribute when you will learn
Cascading Style Sheet (CSS). So for now you can avoid it.
The value of the attribute may
also be a space-separated list of class names.
Example −
class = "className1
className2 className3"
The style Attribute
The style attribute allows you to
specify Cascading Style Sheet (CSS) rules within the element.
<!DOCTYPE html>
<html>
<head>
<title>The style
Attribute</title>
</head>
<body>
<p style = "font-family:arial;
color:#FF0000;">style attribute</p>
</body>
</html>
This will produce the following
result −
At this point of time, we are not
learning CSS, so just let's proceed without bothering much about CSS. Here, you
need to understand what are HTML attributes and how they can be used while
formatting content.
Internationalization Attributes
There are three
internationalization attributes, which are available for most (although not
all) XHTML elements.
- dir
- lang
- xml:lang
The dir Attribute
The dir attribute allows you to
indicate to the browser about the direction in which the text should flow. The
dir attribute can take one of two values, as you can see in the table that
follows −
Value Meaning
ltr Left to right (the default value)
rtl Right to left (for languages such as Hebrew or Arabic
that are read right to left)
Example
<!DOCTYPE html>
<html dir = "rtl">
<head>
<title>Display
Directions</title>
</head>
<body>
This is how IE 5 renders right-to-left
directed text.
</body>
</html>
This will produce the following
result −
When dir attribute is used within
the <html> tag, it determines how text will be presented within the
entire document. When used within another tag, it controls the text's direction
for just the content of that tag.
The lang Attribute
The lang attribute allows you to
indicate the main language used in a document, but this attribute was kept in
HTML only for backwards compatibility with earlier versions of HTML. This
attribute has been replaced by the xml:lang attribute in new XHTML documents.
The values of the lang attribute
are ISO-639 standard two-character language codes. Check HTML Language Codes:
ISO 639 for a complete list of language codes.
Example
<!DOCTYPE html>
<html lang = "en">
<head>
<title>English Language
Page</title>
</head>
<body>
This page is using English Language
</body>
</html>
This will produce the following
result −
The xml:lang Attribute
The xml:lang attribute is the
XHTML replacement for the lang attribute. The value of the xml:lang attribute
should be an ISO-639 country code as mentioned in previous section.
Generic Attributes
Here's a table of some other
attributes that are readily usable with many of the HTML tags.
Attribute Options Function
align right,
left, center Horizontally
aligns tags
valign top,
middle, bottom Vertically
aligns tags within an HTML element.
bgcolor numeric,
hexidecimal, RGB values Places a
background color behind an element
background URL Places
a background image behind an element
id User
Defined Names
an element for use with Cascading Style Sheets.
class User
Defined Classifies
an element for use with Cascading Style Sheets.
width Numeric
Value Specifies
the width of tables, images, or table cells.
height Numeric
Value Specifies
the height of tables, images, or table cells.
title User
Defined "Pop-up"
title of the elements.
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