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HTML 5 <colgroup> tag

Definition and Usage

Defines groups of table columns. With this element, you can group columns for formatting. This element is only valid inside the <table> tag. 

Differences Between HTML 4.01 and HTML 5

Most of the attributes from 4.01 are no longer supported

Tips and Notes

Note: The colgroup element can only contain col elements.

Note: The colgroup element does not create columns. To create columns, you must specify td elements within a tr element.

Tip: Use this element if you want to specify the same attribute values to a group of columns.

Tip: Use the <col> element when you want to specify different attribute values to more than one table column.

Example

Source Output
<table>
<colgroup span="3" style="color:red">
</colgroup>
<tr>
<td>1</td>
<td>2</td>
<td>3</td>
<td>4</td>
</tr>
<tr>
<td>1</td>
<td>2</td>
<td>3</td>
<td>4</td>
</tr>
</table>
1 2 3 4
1 2 3 4

Attributes

Attribute Value Description 4 5
align right
left
center
justify
char		 Defines the horizontal alignment of the content in the table cell, in the column 4  
char character Defines a character to use to align text on (use with align="char") 4  
charoff pixels
%		 Defines an alignment offset to the first character to align on, as set with char 4  
span number Defines the number of columns the <col> should span 4 5
valign top
middle
bottom
baseline		 Defines the vertical alignment of the content in the table cell, in the column 4  
width %
pixels
relative_length		 Defines the width of the column.
Note: Overrides the width set in <colgroup>		 4  

Standard Attributes

class, contenteditable, contextmenu, dir, draggable, id, irrelevant, lang, ref, registrationmark, tabindex, template, title

For a full description, go to Standard Attributes in HTML 5.

Event Attributes

onabort, onbeforeunload, onblur, onchange, onclick, oncontextmenu, ondblclick, ondrag, ondragend, ondragenter, ondragleave, ondragover, ondragstart, ondrop, onerror, onfocus, onkeydown, onkeypress, onkeyup, onload, onmessage, onmousedown, onmousemove, onmouseover, onmouseout, onmouseup, onmousewheel, onresize, onscroll, onselect, onsubmit, onunload

For a full description, go to Event Attributes in HTML 5.

From http://www.w3schools.com (Copyright Refsnes Data)