Javascript脚本

Question

<script language="javascript">
function loadThreadFollow(t_id,b_id){
var targetImg =eval("document.all.followImg" + t_id);
var targetDiv =eval("document.all.follow" + t_id);

if ("object"==typeof(targetImg)){
if (targetDiv.style.display!='block'){
targetDiv.style.display="block";

}else{
targetDiv.style.display="none";
}
}
}
</script>
请问高手 if("object"==typeof(targetImg)这句是什么意思...

Answer 1

如果targetImg的变量类型为object(对象)