创建基于Bootstrap的下拉菜单的DropDownList的JQuery插件

<script>
(function($){ 
jQuery.fn.DropDownList = function(options) {
//设置插件的默认属性  
var defaults ={   
InputName:"Q",   
ButtonText:"示例",   
ReadOnly:true,   
MaxHeight:-1,   
onSelect:$.noop(),  
}  
var options = $.extend(defaults,options);  
return this.each(function(){   
var o=options;   
var Obj=$(this);   
var S="<div class='input-group'>";   
S = S + "<input type='text' class='form-control' name='" + o.InputName + "' id='" + o.InputName + "' />";   
S = S + "<div class='input-group-btn'>";   
S = S + "<button type='button' class='btn btn-default dropdown-toggle' data-toggle='dropdown'>" + o.ButtonText + "<span class='caret'></span></button>";   
S = S + "<ul class='dropdown-menu dropdown-menu-right' role='menu'>"; 
   //可以由Sections参数或Items参数设置下拉条目，Sections的优先级比Items高   
if (o.Sections!== undefined)   
{    $.each(o.Sections,function(n,value){           
//从第2节开始，在每节的顶部添加一条分割线     
if (n>0) { S=S + "<li class='divider'></li>"; }     
//如果设置了ItemHeader参数，则给该节添加标题文本     
if (value.ItemHeader!==undefined) { S = S + "<li class='dropdown-header'>" + value.ItemHeader + "</li>"; }     
CreateItem(value);    
});   
}   
else   
{    
CreateItem(o);   
}    
var SelText="";   
var SelData="";   
function CreateItem(Items)   
{    
$.each(Items.Items,function(n,Item){    
//如果ItemData参数没有定义，则把ItemText参数传给ItemDate     
if (Item.ItemData===undefined) {Item.ItemData=Item.ItemText;}     
S=S + "<li><a href='#' ItemData='" + Item.ItemData + "' >" + Item.ItemText + "</a></li>";     
//如果设置了Selected参数，则获取该条目的ItemDada和ItemText。     
//如果有多个条目设置该参数，则获取的是满足条件最后一个条目     
if (Item.Selected==true) { SelText=Item.ItemText;SelData=Item.ItemData;}   
});   
}     
S =S + "</ul></div></div>";   
Obj.html(S);    
var Input=Obj.find("input");   
//如果有条目设置Selected参数，则调用设置活动条目的函数   
if (SelText!="") { SetData(SelText,SelData); }    
//给所有的条目绑定单击事件，单击后调用设置活动条目的函数   
Obj.find("a").bind("click", function(e) {SetData($(this).html(),$(this).attr("ItemData"));});   
//如果ReadOnly参数设置为true，则屏蔽掉文本框的相关事件，使得文本框不能编辑。（而又显示为激活状态）  
if (o.ReadOnly==true)   
{    
Input.bind("cut copy paste keydown", function(e) {e.preventDefault();});   
}    
//设置MaxHeight参数后（大于0），则设置下拉菜单的最大高度，若条目过多，会出现垂直滚动条  
if (o.MaxHeight>0)   
{    
var UL=Obj.find("ul");    
if (UL.height()>o.MaxHeight)    
{UL.css({'height':o.MaxHeight,'overflow':'auto'});} 
}    
function SetData(Text,Data)   
{    
Input.val(Text);    
if (o.onSelect) 
{ o.onSelect(o.InputName,Data); 
}  
}     
}); 
}
})(jQuery);
</script>

function ShowData(InputName,Data)
{ 
alert(InputName + ":" + Data); 
}
$("#DropDownList").DropDownList( 
{  
InputName:"Q",  
ButtonName:"参考",  
onSelect : function(I,Data)   
{    
ShowData(I,Data);   
},  
Items:[   
{ItemText:"示例1",ItemData:"Demo1",Selected:true},   
{ItemText:"示例2",ItemData:"Demo2"},   
{ItemText:"示例3",ItemData:"Demo3"}  
] 
});

function ShowData(InputName,Data)
{ 
alert(InputName + ":" + Data); 
}$("#DropDownList").DropDownList( 
{  InputName:"Q",  
ButtonText:"参考",  
onSelect : function(I,Data)   
{    
ShowData(I,Data);   
},  
Sections:[   
{    
ItemHeader:"全部",    
Items:[     
{ItemText:"全部",ItemData:"All"}    
]   
},   
{    
Items:[    
{ItemText:"示例1",ItemData:"Demo1",Selected:true},  
{ItemText:"示例2"
}    
]   
}  
] 
});

function ShowData(InputName,Data)
{ 
alert(InputName + ":" + Data); 
}
$("#DropDownList").DropDownList( 
{  
InputName:"Q",  
ButtonText:"参考",  
MaxHeight:310,  
onSelect : function(I,Data)   
{    
ShowData(I,Data);   
},  
Sections:[   
{    
ItemHeader:"直辖市",    
Items:[     
{ItemText:"北京",ItemData:"Beijing"},     
{ItemText:"上海",ItemData:"Shanghai",Selected:true},     
{ItemText:"天津",ItemData:"Tianjin"},     
{ItemText:"重庆",ItemData:"Chongqing"}    
]   
},   
{    
ItemHeader:"华东地区",    
Items:
[     
{ItemText:"山东",ItemData:"Shandong"},     
{ItemText:"江苏",ItemData:"Jiangsu"},     
{ItemText:"安徽",ItemData:"Anhui"},     
{ItemText:"浙江",ItemData:"Zhejiang"},     
{ItemText:"福建",ItemData:"Fujian"}    
]  
},   
{  
ItemHeader:"华南地区",    
Items:[     
{ItemText:"广东",ItemData:"Guangdong"},     
{ItemText:"广西",ItemData:"Guangxi"},     
{ItemText:"海南",ItemData:"Hainan"}    
]   
},   
{    
ItemHeader:"华中地区",    
Items:[     
{ItemText:"湖北",ItemData:"Hubei"},     
{ItemText:"湖南",ItemData:"Hunan"},     
{ItemText:"河南",ItemData:"Henan"},     
{ItemText:"江西",ItemData:"Jiangxi"}   
]   
},   
{    
ItemHeader:"华北地区",    
Items:[     
{ItemText:"河北",ItemData:"Hebei"},     
{ItemText:"山西",ItemData:"Shanxi"},     
{ItemText:"内蒙古",ItemData:"Neimenggu"}    
]   
},   
{    
ItemHeader:"西北地区",    
Items:[     
{ItemText:"宁夏",ItemData:"Ningxia"},     
{ItemText:"新疆",ItemData:"Xinjiang"},     
{ItemText:"青海",ItemData:"Qinghai"},     
{ItemText:"陕西",ItemData:"Shaanxi"},     
{ItemText:"甘肃",ItemData:"Gansu"},    
]   
},   
{    
ItemHeader:"西南地区",    
Items:[     
{ItemText:"四川",ItemData:"Sichuan"},     
{ItemText:"云南",ItemData:"Yunnan"},    
{ItemText:"贵州",ItemData:"Guizhou"},    
{ItemText:"西藏",ItemData:"Xizang"}    
]   
},   
{    
ItemHeader:"东北地区",   
Items:[     
{ItemText:"辽宁",ItemData:"Liaoning"},     
{ItemText:"吉林",ItemData:"Jilin"},     
{ItemText:"黑龙江",ItemData:"Heilongjiang"}    
]   
}  
] 
});