W3School TIY Editor
W3School 在线教程
改变方向
暗黑模式
运行代码
<!DOCTYPE html> <html> <head> <style> table,th,td { border:1px solid black; } </style> </head> <body> <table> <colgroup> <col id="myCol" span="2" style="background-color:red"> <col style="background-color:yellow"> </colgroup> <tr> <th>ISBN</th> <th>Title</th> <th>Price</th> </tr> <tr> <td>3476896</td> <td>My first HTML</td> <td>$53</td> </tr> <tr> <td>5869207</td> <td>My first CSS</td> <td>$49</td> </tr> </table> <p>请点击按钮，返回列的 span 属性的值。</p> <p id="demo"></p> <button onclick="myFunction()">试一下</button> <script> function myFunction() { var x = document.getElementById("myCol").span; document.getElementById("demo").innerHTML=x; } </script> </body> </html>