Javascript实现动态菜单添加的实例代码_javascript技巧

先来看看效果：

Html源码：

Province：

Please Choose Province
HeBei
ShanDong


City：



Area：

Javascript源码

$(document).ready(function () {
//找到三个下拉框
var ProvinceSelect = $(".Province").children("select");
var CitySelect = $(".City").children("select");
var AreaSelect = $(".Area").children("select");
var AddressSelect=$(".AddressSelect");
//给第二个下拉框注册事件
ProvinceSelect.change(function () {
//1、获取当前下拉框的值
var ProvinceValue = $(this).val();
//1.1只要第一个下拉框内容有变化，第三个下拉框就要隐藏起来
AreaSelect.parent().hide();
AddressSelect.hide();
AddressSelect.html("");
//2、如果值不为空，则显示城市下拉框
if (ProvinceValue != "") {
CitySelect.html("");
$("Please Choose City").appendTo(CitySelect);
switch(ProvinceValue)
{
//实际项目中，这个城市数组肯定是在服务器获取的，这里为了简便，我就直接自定义了一个数组
//如果追求完美，这里还可以加一道缓存，防止重复获取
case "HeBei":
var CityOfHeBei=["ShiJiaZhuang","CangZhou","LangFang"];
for(var i=0;i $(""+CityOfHeBei[i]+"").appendTo(CitySelect);
}
break;
case "ShanDong":
var CityOfShanDon=["JiNan","DeZhou","QingDao"];
for(var i=0;i $(""+CityOfShanDon[i]+"").appendTo(CitySelect);
}
break;
}
CitySelect.parent().show();
} else {
CitySelect.parent().hide();
}
});
//给第二个下拉框注册事件
CitySelect.change(function () {
var CityValue = $(this).val();
AddressSelect.hide();
AreaSelect.parent().hide();
AddressSelect.html("");
if (CityValue != "") {
AreaSelect.html("");
$("Please Choose Area").appendTo(AreaSelect);
switch(CityValue)
{
//实际项目中，这个区数组肯定是在服务器获取的，这里为了简便，我就直接自定义了一个数组
//如果追求完美，这里还可以加一道缓存，防止重复获取
case "ShiJiaZhuang":
var AreaOfCity=["GaoXinQu","KaiFaQu","XinHuaQu"];
for(var i=0;i $(""+AreaOfCity[i]+"").appendTo(AreaSelect);
}
break;
case "CangZhou":
var AreaOfCity=["XinHuaQu","YunHeQu"];
for(var i=0;i $(""+AreaOfCity[i]+"").appendTo(AreaSelect);
}
break;
case "LangFang":
var AreaOfCity=["AnCiQu","GuangYangQu"];
for(var i=0;i $(""+AreaOfCity[i]+"").appendTo(AreaSelect);
}
break;
case "QingDao":
var AreaOfCity=["GaoXinQu","KaiFaQu","XinHuaQu"];
for(var i=0;i $(""+AreaOfCity[i]+"").appendTo(AreaSelect);
}
break;
case "DeZhou":
var AreaOfCity=["XinHuaQu","YunHeQu"];
for(var i=0;i $(""+AreaOfCity[i]+"").appendTo(AreaSelect);
}
break;
case "JiNan":
var AreaOfCity=["AnCiQu","GuangYangQu"];
for(var i=0;i $(""+AreaOfCity[i]+"").appendTo(AreaSelect);
}
break;
}
AreaSelect.parent().show();
} else {
AreaSelect.parent().hide();
}
});
AreaSelect.change(function(){
var AreaValue=$(this).val();
AddressSelect.html("");
if (AreaValue!=""){
$("The Address Is --Province: "+ProvinceSelect.val()+" City: "+CitySelect.val()+" Area: "+AreaSelect.val()+"").appendTo(AddressSelect);
AddressSelect.show();
//alert("The Address Is Province: "+ProvinceSelect.val()+" City: "+CitySelect.val()+" Area: "+AreaSelect.val());
}
})
});

这里还引用了Jquery，貌似实现这个效果，用不用都无所谓，最近为了熟悉Jquery的用法，所以就加上了。