select 无限级联动。省市县三级联动。jquery插件

  

/*

省市县 三级联动， 后台提取json数据
<script src="res/PCASelect.js" type="text/javascript"></script>
<script type="text/javascript">
    $(document).ready(function() {
        var defaults = {
            url: 'PCAget.ashx?code=',    //后台json处理文件
            sid: 'PP1,CC1,AA1',             //select的id
            dv: '350000,,',                    //初始值
            ft: '...请选择...,,'        //生成selec的第一项 文本
        };
        $("kk").PCA(defaults);
    });  
</script>



后台文件：PCAget.ashx
<%@ WebHandler Language="C#" Class="PCAget" %>
using System;
using System.Web;
using System.Text;
using System.Data;
using LC.Data.Helper;

public class PCAget : IHttpHandler {
    public void ProcessRequest (HttpContext context) {
        // 数组   [{"id":"275","name":"A1"},{"id":"319","name":"A2"},{"id":"322","name":"A3"}]
        string code = context.Request["code"];
        string strSQL = "select * from s_PCA where parent='" + code + "'  order by Sort ";

        DataTable dt = appData.Instance().ExecuteDataset(strSQL).Tables[0];
        StringBuilder strClass = new StringBuilder();
        if (dt != null)
        {
            strClass.Append("[");
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                strClass.Append("{");
                strClass.Append("\"id\":\"" + dt.Rows[i]["code"].ToString() + "\",");
                strClass.Append("\"name\":\"" + dt.Rows[i]["name"].ToString() + "\"");

                if (i != dt.Rows.Count - 1)
                {
                    strClass.Append("},");
                }
            }
        }
        strClass.Append("}");
        strClass.Append("]");      
        context.Response.ContentType = "application/json";
        context.Response.ContentEncoding = Encoding.UTF8;
        context.Response.Write(strClass.ToString());
        context.Response.End();
    }
    public bool IsReusable {
        get {
            return false;
        }
    }
}


*/


(function($) {
    var defaults = {
        url: 'PCAget.ashx?code=',    //后台json处理文件
        sid: 'PP,CC,AA',             //select的id
        dv: ',,',                    //初始值
        ft: '...请选择...,,',        //生成selec的第一项 文本
        fv: ',,',                    //生成selec的第一项 值
        pid: 0                       //最顶级的父ID ，用于后台处理文件
    };

    $.fn.PCA = function(options) {
        //配置参数
        defaults = $.extend({}, defaults, options);
        var sid = defaults.sid.split(',');
        defaults.len = sid.length;

        GetA("", defaults.pid); //初始化

        //设置change事件
        for (var i = 0; i < sid.length; i++) {
            $("#" + sid[i]).change(function() {
                GetA($(this).attr("id"), $(this).attr("value"))
            });
        }
    };

    function GetA(str_id, pid) {
        var arrSid = defaults.sid.split(',');
        var arrDv = defaults.dv.split(',');
        var arrFt = defaults.ft.split(',');
        var arrFv = defaults.fv.split(',');

        //找出自己
        var self;
        var kk = 0;
        if (str_id != "") {
            while (kk <= arrSid.length) {
                kk++;
                if (arrSid[kk - 1] == str_id)
                    break;
            }
        }
        self = $("#" + arrSid[kk]);

        //清空从自己开始之后所有项
        for (var i = kk; i <= arrSid.length; i++) {
            $("#" + arrSid[i]).html("");
        }

        //当前下拉框的第一个选择项
        if (arrFt[kk] != "")
            self.append("<option value='" + arrFv[kk] + "'>" + arrFt[kk] + "</option>");

        //添加option
        $.getJSON(defaults.url + pid, function(data) {
            for (var i = 0; i < data.length; i++) {
                var $opt = $("<option></option>").val(data[i].id).html(data[i].name);
                if (arrDv[kk] == data[i].id) $opt.attr("selected", "selected");
                self.append($opt);
            };

            //孩子下拉框
            if (arrSid[kk + 1] != undefined)
                GetA(arrSid[kk], self.attr("value"));
        });
    }
})(jQuery);