你的sel里面都没有sel2,sel3的内容,比较麻烦啊.参考下下面的代码: <!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=""> <script type="text/javascript"> function test() { var em=document.getElementById("sel"); var em1=document.getElementById("sel1"); var em2=document.getElementById("sel2"); var em3=document.getElementById("sel3"); var sel=em.options[em.selectedIndex].text; var sel1=em1.options[em1.selectedIndex].text; var sel2=em2.options[em2.selectedIndex].text; var sel3=em3.options[em3.selectedIndex].text; if(sel1==123) { var option=document.createElement("option"); option.value=sel2; option.innerHTML=sel2; em.appendChild(option); em.options[em.selectedIndex].text=sel2; } else if(sel1==456) { var option=document.createElement("option"); option.value=sel3; option.innerHTML=sel3; em.appendChild(option); em.options[em.selectedIndex].text=sel3; }
<textarea id="test"></textarea>
<select onchange='document.getElementById("test").innerHTML=this.options[this.selectedIndex].value;'>
<option value="123">123</option>
<option value="456">456</option>
</select>
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
<script type="text/javascript">
function test()
{
var em=document.getElementById("select");
var option=em.options[em.selectedIndex].text;
document.getElementById("id").value=option;
}
</script>
</HEAD> <BODY>
<textArea id="id" name="text">
</textArea>
<select id="select" onchange="test();">
<option>1</option>
<option>2</option>
<option>3</option>
</select>
</BODY>
</HTML>
<head>
<title>test</title>
<script>
function change() {
var sel = document.getElementById("sel");
var area = document.getElementById("area");
area.innerHTML += sel.value;
}
</script>
</head>
<body>
<select id="sel" onchange="change()">
<option value="123">123</option>
<option value="456">456</option>
</select>
<textarea id="area"></textarea>
</body>
</html>
<select id="sel1">
<option value="123">123 </option>
<option value="456">456 </option>
</select>
<select id="sel">
<option value="123">123 </option>
<option value="456">456 </option>
</select>
<select id="sel2">
<option value="123">321</option>
<option value="456">654</option>
</select>
<select id="sel3">
<option value="123">213</option>
<option value="456">456 </option>
</select>
我想 在选中123的时候 在sel里显示sel2的内容
选中456的时候 在sel里显示sel3的内容
<!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="">
<script type="text/javascript">
function test()
{
var em=document.getElementById("sel");
var em1=document.getElementById("sel1");
var em2=document.getElementById("sel2");
var em3=document.getElementById("sel3"); var sel=em.options[em.selectedIndex].text;
var sel1=em1.options[em1.selectedIndex].text;
var sel2=em2.options[em2.selectedIndex].text;
var sel3=em3.options[em3.selectedIndex].text; if(sel1==123)
{
var option=document.createElement("option");
option.value=sel2;
option.innerHTML=sel2;
em.appendChild(option);
em.options[em.selectedIndex].text=sel2;
}
else if(sel1==456)
{
var option=document.createElement("option");
option.value=sel3;
option.innerHTML=sel3;
em.appendChild(option);
em.options[em.selectedIndex].text=sel3;
}
}
</script>
</HEAD> <BODY>
<select id="sel1" onchange="test();">
<option value="123">123 </option>
<option value="456">456 </option>
</select>
<select id="sel">
<option value="123">123 </option>
<option value="456">456 </option></select>
<select id="sel2">
<option value="123">321 </option>
<option value="456">654 </option>
</select>
<select id="sel3">
<option value="123">213 </option>
<option value="456">456 </option>
</select> </BODY>
</HTML>
<select id="sel1" onchange='document.getElementById("sel").innerHTML=this.options[this.selectedIndex].value;'>
<option value="选择1">选择1 </option>
<option value="选择2">选择2 </option>
</select> <select id="sel2" onchange='document.getElementById("sel").innerHTML=this.options[this.selectedIndex].value;'>
<option value="选择3">选择3 </option>
<option value="选择4">选择4</option>
</select>
<select id="sel3" onchange='document.getElementById("sel").innerHTML=this.options[this.selectedIndex].value;'>
<option value="选择5">选择5 </option>
<option value="选择6">选择6</option>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Untitled Document</title>
<script type="text/javascript">
/**
* author: develop_design_level
* date: 2009-10-28
* @param {Object} id
*/
function $(id){
if(document.getElementById){
return document.getElementById(id);
}else{
return document.all.id;
}
}
window.onload = function(){
$('selId').onchange = function(){
var str = this.options[this.selectedIndex].text;
$('txtId').value = str;
};
};
</script>
</head>
<body>
<select id="selId">
<option value="-1">===请选择===</option>
<option value="1">==1==</option>
<option value="2">==2==</option>
<option value="3">==3==</option>
<option value="4">==4==</option>
<option value="5">==5==</option>
</select>
<br/>
<textarea id="txtId"></textarea>
</body>
</html>-------- 结贴,给分 ----------
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Untitled Document</title>
<script type="text/javascript">
/**
* author: develop_design_level
* date: 2009-10-28
* @param {Object} id
*/
function $(id){
if(document.getElementById){
return document.getElementById(id);
}else{
return document.all.id;
}
}
window.onload = function(){
$('selId').onchange = function(){
var str = this.options[this.selectedIndex].text;
$('txtId').value = str;
};
};
</script>
</head>
<body>
<select id="selId">
<option value="-1">===请选择===</option>
<option value="1">==1==</option>
<option value="2">==2==</option>
<option value="3">==3==</option>
<option value="4">==4==</option>
<option value="5">==5==</option>
</select>
<br/>
<textarea id="txtId"></textarea>
</body>
</html>