What is the purpose of the “alt” attribute of “img”?
时间: 2024-05-23 14:13:10 浏览: 65
The "alt" attribute of the "img" tag provides alternative text to describe the content of an image. It is used when the image cannot be displayed on a webpage, such as when a user is using a screen reader or when the image fails to load. The purpose of the "alt" attribute is to provide a text alternative that conveys the same information as the image so that users with visual impairments or other disabilities can understand the content of the page. Additionally, search engines use the "alt" attribute to understand the content of the image and to improve the page's search engine optimization (SEO).
相关问题
What is the purpose of the “rowspan” attribute of the “td” element?
The "rowspan" attribute of the "td" element in HTML is used to specify the number of rows that a cell should span. This attribute is useful when you want to merge two or more adjacent cells in a table into a single cell that spans multiple rows.
For example, if you have a table with three rows and three columns, and you want to merge the cells in the first column of the first two rows into a single cell, you can use the "rowspan" attribute. You would set the "rowspan" attribute of the first cell to "2", indicating that it should span two rows. This would cause the first two rows of the table to appear as if they have only two cells in the first column, instead of three.
Here is an example of how to use the "rowspan" attribute:
```
<table>
<tr>
<td rowspan="2">This cell spans two rows</td>
<td>Cell 1</td>
<td>Cell 2</td>
</tr>
<tr>
<td>Cell 3</td>
<td>Cell 4</td>
</tr>
<tr>
<td>Cell 5</td>
<td>Cell 6</td>
<td>Cell 7</td>
</tr>
</table>
```
In this example, the first cell spans two rows, so the first two rows of the table appear to have only two cells in the first column.
What is the format of an inline style sheet?
An inline style sheet is defined using the `style` attribute within an HTML element. The format typically looks like this:
```html
<element style="property: value; property: value;">
```
For example, to set the color of a paragraph to red, you would use:
```html
<p style="color: red;">This is a red paragraph.</p>
```
Note that multiple CSS properties can be set within the same `style` attribute by separating them with a semicolon.