html 标签的自定义属性应用
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Document</title> <script> window.onload = function(){ var aBtn = document.getElementsByTagName('input'); console.log(aBtn); var arr = ['A','B','C','D']; for(var i=0; i< aBtn.length; i++){ aBtn[i].num = 0; aBtn[i].onclick = function(){ this.value = arr[this.num]; this.num++; if (this.num === arr.length){ this.num = 0; } }; }; }; </script> </head> <body> <input type="button" value="0"> <input type="button" value="0"> <input type="button" value="0"> </body> </html>