编辑代码:
查看结果 »
试一试 - ©
w3ii.com
<!DOCTYPE html> <html> <body> <form> <select id="mySelect" size="4"> <option>Apple</option> <option>Orange</option> <option>Pineapple</option> <option>Banana</option> </select> </form> <p>Click the button to display the number of options in the drop-down list.</p> <button onclick="myFunction()">Try it</button> <p id="demo"></p> <script> function myFunction() { var x = document.getElementById("mySelect").options.length; document.getElementById("demo").innerHTML = "Found " + x + " options in the list."; } </script> </body> </html>