Tham khảo tài liệu 'pro css techniques- p6', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 222 CHAPTER 10 STYLING TABLES agent understand which cells are related to one another. Again this is especially helpful to screen readers and other assistive technology. It helps them read or display tables more logically. Our example table with the scope attribute added might look something like this table tr th scope col Name th th scope col Affiliation th th scope col abbr URL Website URL th tr tr td scope row Jeff Croft td td World Online td td http td tr tr td scope row Ian Lloyd td td Accessify td td http td tr tr td scope row Dan Rubin td td Webgraph td td http td tr table Note that the element containing the names of individuals is marked up as a td not a th but is still assigned the scope attribute. Because our names are data values in this table and not simply generic labels they should be table data cell elements rather than table header elements. However they still provide context for the rest of the information in the row so the addition of the scope attribute is appropriate. Assigning scope in Complex Tables As your tables become more complex you may find cases where the header information for a particular data cell is not the same row or column as that cell or where three or more headers apply to a single data cell. In these cases scope breaks down and you ll need to use the headers attribute on your cells. By assigning a unique id to your headers you can then reference them as the context for a data cell. Our example is simple enough that scope works fine but here s an example of how it looks using headers instead table tr th id name Name th th id affiliation Affiliation th th id url abbr URL Website URL th tr tr CHAPTER 10 STYLING TABLES 223 td id jeff_croft Jeff Croft td td headers jeff_croft affiliation World Online td td headers jeff_croft url http td tr tr td id ian_lloyd Ian Lloyd td td headers ian_lloyd affiliation Accessify td td headers ian_lloyd url http td tr tr
