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/展開與收起效果
為何我將ID放在注釋一的位置,就不能成功?
2015-07-27
源自:展開與收起效果 3-4
正在回答
<div?id="ad">? ???<img?id="adcon"?src="ad.png"?width="960"?height="385"/>? </div> <div?id="content"><img?src="數(shù)字商品-10-23.jpg"?/></div> <script> //全局變量 var?oAd?????=?document.getElementById('ad'); var?oAdcon??=?document.getElementById('adcon'); var?h?=?0; var?step?=?5; var?maxH?=?oAdcon.height; function?adDown(){ oAd.style.height?=?h?+'px'; ????oAd.style.display?=?'block'; if(h<maxH){ h+=step; setTimeout(adDown,1); }else{ setTimeout(adUp,3000); } } function?adUp(){ if(h>0){ h-=step; oAd.style.height?=?h?+'px'; setTimeout(adUp,1); } } setTimeout(adDown,3000); </script>
<div?id="ad">?
???<img?id="adcon"?src="ad.png"?width="960"?height="385"/>?
</div>
<div?id="content"><img?src="數(shù)字商品-10-23.jpg"?/></div>
<script>
//全局變量
var?oAd?????=?document.getElementById('ad');
var?oAdcon??=?document.getElementById('adcon');
var?h?=?0;
var?step?=?5;
var?maxH?=?oAdcon.height;
function?adDown(){
oAd.style.height?=?h?+'px';
????oAd.style.display?=?'block';
if(h<maxH){
h+=step;
setTimeout(adDown,1);
}else{
setTimeout(adUp,3000);
}
function?adUp(){
if(h>0){
h-=step;
setTimeout(adUp,1);
setTimeout(adDown,3000);
</script>
還有個(gè)小問題,這是另一段代碼,script中依然是外邊全局,但這個(gè)是可以執(zhí)行成功的???
按照從上而下執(zhí)行的順序,定義pn時(shí)還未能讀取到html文件中id為pn的元素內(nèi)容,所以全局定義pn變量時(shí),pn為空
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2015-08-17
<div?id="ad">?
???<img?id="adcon"?src="ad.png"?width="960"?height="385"/>?
</div>
<div?id="content"><img?src="數(shù)字商品-10-23.jpg"?/></div>
<script>
//全局變量
var?oAd?????=?document.getElementById('ad');
var?oAdcon??=?document.getElementById('adcon');
var?h?=?0;
var?step?=?5;
var?maxH?=?oAdcon.height;
function?adDown(){
oAd.style.height?=?h?+'px';
????oAd.style.display?=?'block';
if(h<maxH){
h+=step;
setTimeout(adDown,1);
}else{
setTimeout(adUp,3000);
}
}
function?adUp(){
if(h>0){
h-=step;
oAd.style.height?=?h?+'px';
setTimeout(adUp,1);
}
}
setTimeout(adDown,3000);
</script>
2015-07-27
還有個(gè)小問題,這是另一段代碼,script中依然是外邊全局,但這個(gè)是可以執(zhí)行成功的???
2015-07-27
按照從上而下執(zhí)行的順序,定義pn時(shí)還未能讀取到html文件中id為pn的元素內(nèi)容,所以全局定義pn變量時(shí),pn為空