位置放倒了!当js去获取span的时候,text还没出来!如下就OK<body>
<span id="text" title="title">the text in span</span>
<script type="text/jscript" language="javascript">
var text = document.getElementById("text");
if (text==null)
alert("null");
alert(text.innerHTML);
</script>
</body>
<span id="text" title="title">the text in span</span>
<script type="text/jscript" language="javascript">
var text = document.getElementById("text");
if (text==null)
alert("null");
alert(text.innerHTML);
</script>
</body>
<body><span id="text" title="title">the text in span</span><script type="text/javascript">
<!--
var text = document.getElementById("text");
if (text==null)
alert("null");
//-->
</script></body>
那再问一下,我最终实现的是点击按钮文字和图片同时变换。都写在一个js文件的函数里面,在<head></head>里导入,结果图片能变,文字不行,是不是因为图片和文字加载的时间不同呢?如何改正呢?adImages = new Array(); //开一个新的Array物件,物件名为adImages.
adImages[0] = "images/rb_bottom_image.jpg";
adImages[1] = "images/sample1.jpg";
adImages[2] = "images/sample2.jpg";
text = new Array();
text[0] = "天际经理 资深顾问 陆永红";
text[1] = "天际员工 资深顾问 谭 烨";
text[2] = "天际员工 资深顾问 陈 娟";
var currentAd = 0;
var ImgNum = 2;
function left() {
currentAd = currentAd -1;
if (currentAd == -1) {
currentAd = ImgNum;
}
document.getElementById("adarea").src = adImages[currentAd];
document.getElementById("text").innerHtml = text[currentAd];
}
function right() {
currentAd = currentAd +1;
if (currentAd == ImgNum+1) {
currentAd = 0;
}
document.getElementById("adarea").src = adImages[currentAd];
}
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
</HEAD>
<body>
<img id="adarea" src="" />
<span id="text" title="title">the text in span</span>
<input type="button" onclick="left()" value="<-"><input type="button" onclick="right()" value="->">
<script type="text/jscript" language="javascript">
var text = document.getElementById("text");
if (text==null)
alert("null");
//alert(text.innerHTML);//新的要求,如下:
adImages = new Array(); //开一个新的Array物件,物件名为adImages.
adImages[0] = "images/rb_bottom_image.jpg";
adImages[1] = "images/sample1.jpg";
adImages[2] = "images/sample2.jpg";
text = new Array();
text[0] = "天际经理 资深顾问 陆永红";
text[1] = "天际员工 资深顾问 谭 烨";
text[2] = "天际员工 资深顾问 陈 娟";
var currentAd = 0;
var ImgNum = 2; function left() {
currentAd = currentAd -1;
if (currentAd == -1) {
currentAd = ImgNum;
}
document.getElementById("adarea").src = adImages[currentAd];
document.getElementById("text").innerHTML = text[currentAd];
}function right() {
currentAd = currentAd +1;
if (currentAd == ImgNum+1) {
currentAd = 0;
}
document.getElementById("adarea").src = adImages[currentAd];
document.getElementById("text").innerHTML = text[currentAd];
}</script>
</body>
</HTML>