<col> - HTML（超文本标记语言） 编辑

HTML <col> 元素 定义表格中的列，并用于定义所有公共单元格上的公共语义。它通常位于<colgroup>元素内。

此元素允许使用CSS进行样式列，但只有少数属性将对该列产生影响（请参阅列表的CSS 2.1规范）。

• Content categories None.
• Permitted content None, it is an empty element.
• Tag omission The start tag is mandatory, but, as it is a void element, the use of an end tag is forbidden.
• Permitted parent elements <colgroup> only, though it can be implicitly defined as its start tag is not mandatory. The <colgroup> must not have a span attribute.
• Permitted ARIA rolesNone
• DOM interface HTMLTableColElement

属性

该元素包含一些全局属性 全局属性.

align 已废弃 HTML4.01, 已废弃 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 未实现 (查看 bug 2212).

If this attribute is not set, its value is inherited from the align of the <colgroup> element this <col> element belongs too. If there are none, the left value is assumed.

Note: Do not use this attribute as it is obsolete (not supported) in the latest standard.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 <col> element. Because <td> elements are not descendant of the <col> element, they won't inherit it.
  • If the table doesn't use a colspan attribute, use the td:nth-child(an+b) CSS selector 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 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 未实现.

bgcolor

定义列中对应的每个单元格的背景色。其值是 sRGB 定义的6位16进制代码之一，前缀为 '#'。 也可以使用以下16个预定义的颜色字符:

	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"

注意: 不要使用这个属性, 它是非标准的，并且只实现了IE浏览器中的部分版本: <col> 元素的样式应该使用 CSS. 在<td>元素上使用 CSS 的 background-color 属性即可实现相同效果。

char 已废弃 HTML4.01, 已废弃 HTML5

This attribute is used to set the character to align the cells in a column on. 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. 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 未实现.

charoff 已废弃 HTML4.01, 已废弃 HTML5

This attribute is used to indicate the number of characters to offset the column data from the alignment characters specified by the char attribute. Note: Do not use this attribute as it is obsolete (and not supported) in the latest standard.

span

该属性值为一个正整数，表示该 <col> 元素横跨的列数。默认值为1

valign 已废弃 HTML4.01, 已废弃 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 <col> element. Because <td> elements are not descendant of the <col> element, they won't inherit it.
• If the table doesn't use a colspan attribute, use the td:nth-child(an+b) CSS selector 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 已废弃 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.

示例

详见 <table> 页面 <col> 标签的示例.

规范

Specification	Status	Comment
HTML Living Standard <col>	Living Standard
HTML5 <col>	Recommendation
HTML 4.01 Specification <col>	Recommendation

浏览器兼容性

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

• Desktop
• Mobile

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari
Basic support	1.0	1.0 (1.7 or earlier)	(Yes)	(Yes)	(Yes)
align/valign attribute	?	未实现 bug 915	?	?	?
char/charoff attribute	?	未实现 bug 2212	?	?	?
bgcolor attribute	?	未实现	(Yes)	?	?

Feature	Android	Firefox Mobile (Gecko)	IE Mobile	Opera Mobile	Safari Mobile
Basic support	?	1.0 (1.0)	?	?	?
align/valign attribute	?	未实现 bug 915	?	?	?
char/charoff attribute	?	未实现 bug 2212	?	?	?
bgcolor attribute	?	未实现	?	?	?

相关链接

• Other table-related HTML Elements: <caption>, <colgroup>, <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 '.'.