Ordered list
From Wikipedia, the free encyclopedia
In HTML an ordered list <ol> .. </ol> is a HTML element for a list of items where each item is automatically prefixed by an indication of its position in the list.
An unordered list <ul> .. </ul> is an HTML element for a list of items where each item is prefixed by a fixed symbol, or nothing.
A list-style-type implies the prefixes to be equal or changing, and overrides the distinction between ol and ul.
Examples: decimal (default list-style-type for ol):
<ol> <li>Amsterdam</li> <li>Rotterdam</li> <li>The Hague</li> </ol>
gives
- Amsterdam
- Rotterdam
- The Hague
Contents |
[edit] List style types
Specifying a list-style-type:
lower-alpha:
<ol style="list-style-type: lower-alpha"> <li>Amsterdam</li> <li>Rotterdam</li> <li>The Hague</li> </ol>
gives
- Amsterdam
- Rotterdam
- The Hague
Similarly:
upper-alpha:
- Amsterdam
- Rotterdam
- The Hague
lower-roman:
- Amsterdam
- Rotterdam
- The Hague
upper-roman:
- Amsterdam
- Rotterdam
- The Hague
disc (default list-style-type for 1st-level ul):
- Amsterdam
- Rotterdam
- The Hague
circle (default list-style-type for 2nd-level ul):
- Amsterdam
- Rotterdam
- The Hague
square (default list-style-type for 3rd and higher level ul):
- Amsterdam
- Rotterdam
- The Hague
"none":
- Amsterdam
- Rotterdam
- The Hague
[edit] Starting value
A starting value (in decimal form) can be specified (naturally this has no effect if the prefix does not depend on the item's position in the list):
<ol start="2"> <li>Amsterdam</li> <li>Rotterdam</li> <li>The Hague</li> </ol>
gives
- Amsterdam
- Rotterdam
- The Hague
Similarly for the different style types and a starting value of 2:
list-style-type: lower-alpha
- Amsterdam
- Rotterdam
- The Hague
list-style-type: upper-alpha
- Amsterdam
- Rotterdam
- The Hague
List-style-type: lower-roman
- Amsterdam
- Rotterdam
- The Hague
List-style-type: upper-roman
- Amsterdam
- Rotterdam
- The Hague
[edit] Comparison with a table
Apart from providing automatic numbering, the numbered list also aligns the contents of the items, comparable with using table syntax:
<ol start="9"> <li>Amsterdam</li> <li>Rotterdam</li> <li>The Hague</li> </ol>
gives
- Amsterdam
- Rotterdam
- The Hague
<table> <col span="2" /> <tr><td align="right">9.</td><td>Amsterdam</td></tr> <tr><td align="right">10.</td><td>Rotterdam</td></tr> <tr><td align="right">11.</td><td>The Hague</td></tr> </table>
gives
9. | Amsterdam |
10. | Rotterdam |
11. | The Hague |
This non-automatic numbering has the advantage that if a text refers to the numbers, insertion or deletion of an item does not disturb the correspondence.