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JQuery implementation of cascading drop-down box effect example explanation_jquery
JQuery implementation of cascading drop-down box effect example explanation_jquery
Use JQuery and select to realize the linkage between car manufacturers and car types. The reference process is as follows
Rendering:
Logic analysis diagram:
html code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>级联下拉框效果</title>
<link rel="stylesheet" type="text/css" href="css/chainselect.css">
<script language="javascript" type="text/javascript" src="js/jquery.js"></script>
<script language="javascript" type="text/javascript" src="js/chainselect.js"></script>
</head>
<body>
<div class="car">
<span class="carname">
汽车厂商：
<select>
<option value="">请选择汽车厂商</option>
<option value="BMW">宝马</option>
<option value="Audi">奥迪</option>
<option value="VW">大众</option>
</select>
<img src="/static/imghw/default1.png" data-src="images/pfeil.gif" class="lazy" alt="JQuery implementation of cascading drop-down box effect example explanation_jquery"/>
</span>
<span class="cartype">
汽车类型：
<select></select>
</span>
</div>
</body>
</html>
css code:
.car {
text-align:center;
}
.cartype{
display:none;
} js code:
$(document).ready(function(){
//找到下拉框
var carnameSelect = $(".carname").children("select");
var cartypeSelect = $(".cartype").children("select");
//给下拉框注册事件
carnameSelect.change(function(){
var carnameValue = $(this).val();
if( carnameValue != ""){
//carnameValue不为空的情况接着判断
if(!carnameSelect.data(carnameValue)){
//不在缓冲区中,需要向服务器请求
$.post("ChainSelect",{keyword:carnameValue,type:"top"},function(data){
if (data.length != 0){
//返回的数据不为空
cartypeSelect.html("");
$("<option value=''>请选择汽车类型</option>").appendTo(cartypeSelect);
for(var i = 0;i < data.length; i++ ){
$("<option value =' " + data[i] + " '> "+ data[i] +"</option>").appendTo(cartypeSelect);
}
cartypeSelect.parent().show();
carnameSelect.next().show();
}else{
//返回的数据为空
cartypeSelect.parent().hide();
carnameSelect.next().hide();
}
carnameSelect.data(carnameValue,data);
},"json");
}else{
//在缓冲区中
var data = carnameSelect.data(carnameValue);
if (data.length != 0){
//返回的数据不为空
cartypeSelect.html("");
$("<option value=''>请选择汽车类型</option>").appendTo(cartypeSelect);
for(var i = 0;i < data.length; i++ ){
$("<option value =' " + data[i] + " '> "+ data[i] +"</option>").appendTo(cartypeSelect);
}
cartypeSelect.parent().show();
carnameSelect.next().show();
}else{
//返回的数据为空
cartypeSelect.parent().hide();
carnameSelect.next().hide();
}
}
}else{
//carnameValue为空的情况，隐藏第二个下拉框
cartypeSelect.parent().hide();
carnameSelect.next().hide();
}
});
}); The above is a small example of using JQuery and select to implement cascading drop-down boxes. I hope it will be helpful to everyone's learning.
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