Connected: An Internet Encyclopedia
4.7. The COLGROUP Element

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4.7. The COLGROUP Element

4.7. The COLGROUP Element

   <!ELEMENT colgroup - O (col*)>

   <!ATTLIST colgroup
           %attrs;                    -- id, lang, dir and class --
           span    NUMBER   1         -- default number of columns in --
                                      -- group --
           width   CDATA    #IMPLIED  -- default width for enclosed --
                                      -- COLs --
           %cell.halign;              -- horizontal alignment in --
                                      -- cells --
           %cell.valign;              -- vertical alignment in cells --

The COLGROUP element acts as a container for a group of columns, and allows you to set default properties for these columns. In the absence of a COLGROUP element, all columns in the table are assumed to belong to a single column group. Each COLGROUP element can contain zero or more COL elements. COLGROUP requires a start tag, but the end tag may be omitted. This is useful when defining a sequence of COLGROUP elements, e.g.

           <COL WIDTH="1*">
           <COL WIDTH="2*">
           <COL WIDTH="1*">
           <COL WIDTH="3*">
           <TR> ...

COLGROUP elements can be used with the following attributes:

See earlier description of common attributes.

A positive integer value that specifies a default for how many columns are in this group. This attribute should be ignored if the COLGROUP element contains one or more COL elements. It provides a convenient way of grouping columns without the need to supply COL elements.

Specifies a default width for each of the grouped columns, see standard units. In addition, the "*" suffix denotes relative widths, e.g.

            width=64        width in screen pixels
            width=0.5*      a relative width of 0.5

Relative widths act as constraints on the relative widths of different columns. If a COLGROUP element specifies a relative width of zero, all of the columns in the group should be set to their minimum widths, unless they are associated with a COL element with an overriding WIDTH attribute. When widths are given in absolute units, the user agent can use these to constrain the width of the table. The "*" suffix is used to simplify importing tables from the CALS representation.

Specify values for horizontal and vertical alignment within table cells. See inheritance order of alignment properties.

Next: 4.8. The COL Element

Connected: An Internet Encyclopedia
4.7. The COLGROUP Element