document.getElementByIdx_x=function(id){ if(typeof id =='string') return document.getElementById(id); else throw new error('please pass a string as a id!') }

<div id='box'>9</div> <script> document.getElementByIdx_x=function(id){ if(typeof id =='string') return document.getElementById(id); else throw new error('please pass a string as a id!') } var timer = window.setInterval(function(){ document.getElementByIdx_x('box').innerHTML = parseInt(document.getElementByIdx_x('box').innerHTML) - 1; if(parseInt(document.getElementByIdx_x('box').innerHTML) < 0) { window.clearInterval(timer); window.location = 'http://www.1sucai.cn'; } }, 1000); </script>