HTML Attributes
HTML Class Attribute
The class HTML attribute is used to associate an element with a style sheet, and specifies the class of element, you learn more about the use of the class attribute when you will learn cascading Style sheet(CSS). The value of the attribute may also be a space-separated list of class names. For example.
class=”className1 classname2 classname3”
HTML Style Attribute
The style HTML attribute allows you to specify CSS rules within the element. For example
<p style=”font-family:arial; color:#FF0000;”>Some text… </p>
Generic Attributes
Here’s table of some other attributes that are readily usable with many of HTML’s tags.
| Attribute | Options | Function |
| align | right,left,center | Horizontally aligns tags |
| valign | top,middle,bottom | Vertically aligns tags within an HTMl element. |
| bgcolor | numeric, hexadecimal,RGB values | Places a background color behind an element |
| background | URL | Places an 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 for your element. |
We will see related examples as we will proceed to study other HTML tags.
World wide web Consortium(w3c) recommends lowercase in HTML 4, And demands lowercase tags in XHTML
Attributes
An attribute is used to define the characteristics of an element and is placed inside the element’s opening tag. All attributes are made up of two parts: a name and a value.
The value of the attribute should be put in double quotation marks, and is separated from the name by the equals sign
Many HTML tags have a unique set of their own attributes. Right now we want to focus on a set of generic attributes.
Core Attributes
The four core attributes that can be used on the majority of HTML elements(although not all) are:
- id
- title
- class
- style
HTML id Attribute
The id HTML attribute can be used to uniquely identify any element within a page(or style sheet). 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 webpage(or style sheet), you can use the id attribute to distinguish between elements that have the same name.
For now, the id attribute could be used to distinguish between two paragraph elements, like so:
<p id=”html”> This para explains what is HTML</p>
<p id=”css”>This para explains what is casecading style sheet<\p>
Note that there are some special rules for the value of the id attribute, it must :
Begin with a letter (A.Z or a.z) and can then be followed by any number of letters, digits(0,9), hyphens, underscores, colons, and periods.
Remain unique within that document; no two attributes may have the same value within that HTML document.
HTML Title Attribute
The title HTML attribute gives a suggested title for the element. The behavior of this attribute will depend upon the element that carries it, although it is often displayed as a tooltip or while the element is loading.
Use Lowercase Attributes
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.
Newer versions of (X) HTML will demand lowercase attributes.