Home
JS
JS
Tryit: JAVASCRIPT
运行 ❯
×
Change Orientation
Change Theme, Dark/Light
<!DOCTYPE html> <html> <body> <p>单击该按钮可定位指定值的最后一次出现，从位置 20 开始搜索。</p> <button onclick="myFunction()">试一试</button> <p id="demo"></p> <script> function myFunction() { var str = "Hello planet earth, you are a great planet."; var n = str.lastIndexOf("planet", 20); document.getElementById("demo").innerHTML = n; } </script> </body> </html>