為什么獲得字符串長度的時候this.value可以傳入文本框的值?。?/h1>
name.onkeyup=function(){
??????count.style.visibility="visible";
??????name_length=getlength(this.value);
??????count.innerHTML=name_length+"個字符"
??????if(name_length==0)
??????{
????????count.style.visible="hidden";
??????}
name.onkeyup=function(){
??????count.style.visibility="visible";
??????name_length=getlength(this.value);
??????count.innerHTML=name_length+"個字符"
??????if(name_length==0)
??????{
????????count.style.visible="hidden";
??????}
2015-04-08
你可以嘗試console.log(this)一下，看看this到底是個什么東西，然后你就懂了