<script?type="text/javascript">
????var?num=0;
????var?i;
????function?startCount(){
????????//每次開(kāi)始前,先判斷是否也有一個(gè)定時(shí)在執(zhí)行,如果有就清除掉
????????if(i){
????????????clearTimeout(i);
????????}
????????var?input?=?document.getElementById('count');
????????num?=?parseInt(input.value)?||?num;
????????num=num+1;
????????input.value?=?num;
????????i=setTimeout("startCount()",1000);
????}
????function?stopCount(){
????????clearTimeout(i)
????}
</script>

因?yàn)橹貜?fù)點(diǎn)擊開(kāi)始就是重復(fù)開(kāi)啟定時(shí)器，多個(gè)定時(shí)器同時(shí)運(yùn)行 就會(huì)孌快