Please note, this is a STATIC archive of website developer.mozilla.org from 03 Nov 2016, cach3.com does not collect or store any user information, there is no "phishing" involved.

I volontari di MDN non hanno ancora tradotto questo articolo in Italiano. Registrati per tradurlo tu.

Summary

The HTML Table Column Group Element (<colgroup>) defines a group of columns within a table.

Content categories None.
Permitted content If the span attribute is present: none, it is an empty element.
If the attribute is not present: zero or more <col> element
Tag omission The start tag may be omitted, if it has a <col> element as its first child and if it is not preceded by a <colgroup> whose end tag has been omitted.
The end tag may be omitted, if it is not followed by a space or a comment.
Permitted parent elements A <table> element. The <colgroup> must appear after any optional <caption> element but before any <thead>, <th>, <tbody>, <tfoot> and <tr> element.
DOM interface HTMLTableColElement

Attributes

This element includes the global attributes.

align Deprecated since HTML4.01, Obsolete since HTML5
This enumerated attribute specifies how horizontal alignment of each column cell content will be handled. Possible values are:
  • left, aligning the content to the left of the cell
  • center, centering the content in the cell
  • right, aligning the content to the right of the cell
  • justify, inserting spaces into the textual content so that the content is justified in the cell
  • char, aligning the textual content on a special character with a minimal offset, defined by the char and charoff attributes Unimplemented (see bug 2212).

If this attribute is not set, the left value is assumed. The descendant <col> elements may override this value using their own align attribute.

Note: Do not use this attribute as it is obsolete (not supported) in the latest standard.
  • To achieve the same effect as the left, center, right or justify values:
    • Do not try to set the text-align property on a selector giving a <colgroup> element. Because <td> elements are not descendant of the <colgroup> element, they won't inherit it.
    • If the table doesn't use a colspan attribute, use one td:nth-child(an+b) CSS selector per column, where a is the total number of the columns in the table and b is the ordinal position of this column in the table. Only after this selector the text-align property can be used.
    • If the table does use a colspan attribute, the effect can be achieved by combining adequate CSS attribute selectors like [colspan=n], though this is not trivial.
  • To achieve the same effect as the char value, in CSS3, you can use the value of the char as the value of the text-align property Unimplemented.
bgcolor
This attribute defines the background color of each cell of the columns member of the column group. It is one of the 6-digit hexadecimal code as defined in sRGB, prefixed by a '#'. One of the sixteen predefined color strings, as mentioned below, may be used:
  black = "#000000"   green = "#008000"
  silver = "#C0C0C0"   lime = "#00FF00"
  gray = "#808080"   olive = "#808000"
  white = "#FFFFFF"   yellow = "#FFFF00"
  maroon = "#800000"   navy = "#000080"
  red = "#FF0000"   blue = "#0000FF"
  purple = "#800080"   teal = "#008080"
  fuchsia = "#FF00FF"   aqua = "#00FFFF"
Usage note: Do not use this attribute, as it is non-standard and is only implemented in some versions of Microsoft Internet Explorer; the <colgroup> elements should be styled using CSS. To give a similar effect to the bgcolor attribute, use the CSS property background-color on the relevant <td> elements.
char Deprecated since HTML4.01, Obsolete since HTML5
This attribute specifies the alignment of the content in a column group to a character. Typical values for this include a period (.) when attempting to align numbers or monetary values. If align is not set to char, this attribute is ignored, though it will still be used as the default value for the align of the <col> which are members of this column group.
Note: Do not use this attribute as it is obsolete (and not supported) in the latest standard. To achieve the same effect as the char, in CSS3, you can use the character set using the char attribute as the value of the text-align property Unimplemented.
charoff Deprecated since HTML4.01, Obsolete since HTML5
This attribute is used to indicate the number of characters to offset the column data from the alignment character specified by the char attribute.
Note: Do not use this attribute as it is obsolete (and not supported) in the latest standard.
span
This attribute contains a positive integer indicating the number of consecutive columns the <colgroup> element spans. If not present, its default value is 1.
Note: This attribute is applied on the attributes of the column group, it has no effect on the CSS styling rules associated with it or, even more, to the cells of the column's members of the group.
  • The span attribute may not be present if there are one or more <col> elements within the <colgroup>.
valign Deprecated since HTML4.01, Obsolete since HTML5
This attribute specifies the vertical alignment of the text within each cell of the column. Possible values for this attribute are:
  • baseline, which will put the text as close to the bottom of the cell as it is possible, but align it on the baseline of the characters instead of the bottom of them. If characters are all of the size, this has the same effect as bottom.
  • bottom, which will put the text as close to the bottom of the cell as it is possible;
  • middle, which will center the text in the cell;
  • and top, which will put the text as close to the top of the cell as it is possible.
Note: Do not use this attribute as it is obsolete (and not supported) in the latest standard:
  • Do not try to set the vertical-align property on a selector giving a <colgroup> element. Because <td> elements are not descendant of the <colgroup> element, they won't inherit it.
  • If the table doesn't use a colspan attribute, use the td:nth-child(an+b) CSS selector per column, where a is the total number of the columns in the table and b is the ordinal position of the column in the table. Only after this selector the vertical-align property can be used.
  • If the table does use a colspan attribute, the effect can be achieved by combining adequate CSS attribute selectors like [colspan=n], though this is not trivial.
width in HTML5
This attribute specifies a default width for each column in the current column group. In addition to the standard pixel and percentage values, this attribute might take the special form 0*, which means that the width of each column in the group should be the minimum width necessary to hold the column's contents. Relative widths such as 0.5* also can be used.

Examples

Please see the <table> page for examples on <colgroup>.

Specifications

Specification Status Comment
WHATWG HTML Living Standard
The definition of '<colgroup>' in that specification.
Living Standard  
HTML5
The definition of '<colgroup>' in that specification.
Recommendation  
HTML 4.01 Specification
The definition of '<colgroup>' in that specification.
Recommendation  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 1.0 1.0 (1.7 or earlier) (Yes) (Yes) (Yes)
align/valign attribute ? Not supported bug 915 ? ? ?
char/charoff attribute ? Not supported bug 2212 ? ? ?
bgcolor attribute ? Not supported (Yes) ? ?
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? 1.0 (1.0) ? ? ?
align/valign attribute ? Not supported bug 915 ? ? ?
char/charoff attribute ? Not supported bug 2212 ? ? ?
bgcolor attribute ? Not supported ? ? ?

See also

  • Other table-related HTML Elements: <caption>, <col>, <table>, <tbody>, <td>, <tfoot>, <th>, <thead>, <tr>;
  • CSS properties and pseudo-classes that may be specially useful to style the <col> element:
    • the width property to control the width of the column;
    • the :nth-child pseudo-class to set the alignment on the cells of the column;
    • the text-align property to align all cells content on the same character, like '.'.

Tag del documento e collaboratori

 Ultima modifica di: Sebastianz,