联动下拉框 jquery插件(三)

 

<select id="CategoryFirst" class="ld-select-1" name="CategoryFirst"><option value="">请选择大类</option></select>
<select id="CategorySecond" class="ld-select-1" name="CategorySecond"><option value="">请选择小类</option></select>

 

<script src="../Scripts/jquery-1.6.1.min.js" type="text/javascript"></script>
<script src="../Scripts/jQuery.LiveSelect.js" type="text/javascript"></script>
$(".ld-select-1").ld({ ajaxOptions: { "url": "../Ajax/CategoryHandler.ashx" }, defaultParentId: 1,
    style: { "width": 120 }
});
 if (context.Request.Params["CategoryParentID"] != null)
 {
     sql = String.Format("SELECT CategoryId ,CategoryName  FROM B_Category 
     WHERE CategoryParentID='{0}'", context.Request.Params["CategoryParentID"]);
 }

数据库 单表 id name parentid
json格式 同 前第一篇


插件:
(function ($) {
    $.fn.ld = function (options) {
        var opts;
        var DATA_NAME = "ld";
        //返回API
        if (typeof options == 'string') {
            if (options == 'api') {
                return $(this).data(DATA_NAME);
            }
        }
        else {
            var options = options || {};
            //覆盖参数
            opts = $.extend(true, {}, $.fn.ld.defaults, options);
        }
        if ($(this).size() > 0) {
            var ld = new yijs.Ld(opts);
            ld.$applyTo = $(this);
            ld.render();
            $(this).data(DATA_NAME, ld);
        }
        return $(this);
    }
    var yijs = yijs || {};
    yijs.Ld = function (options) {
        //参数
        this.options = options;
        //起作用的对象
        this.$applyTo = this.options.applyTo && $(this.options.applyTo) || null;
        //缓存前缀
        this.cachePrefix = "data_";
        //写入到选择框的option的样式名	
        this.OPTIONS_CLASS = "ld-option";
        //缓存,为一个对象字面量。
        this.cache = {};
    }
    yijs.Ld.prototype = {
        /**
        * 运行
        * @return {Object} this
        */
        render: function () {
            var _that = this;
            var _opts = this.options;
            if (this.$applyTo != null && this.size() > 0) {
                _opts.style != null && this.css(_opts.style);
                //加载默认数据,向第一个选择框填充数据
                this.load(_opts.defaultLoadSelectIndex, _opts.defaultParentId);
                _opts.texts.length > 0 && this.selected(_opts.texts);
                //给每个选择框绑定change事件
                this.$applyTo.each(function (i) {
                    i < _that.size() - 1 && $(this).bind("change.ld", { target: _that, index: i }, _that.onchange);
                })
            }
            return this;
        },
        texts: function (ts) {
            var that = this;
            var $select = this.$applyTo;
            var _arr = [];
            var txt = null;
            var $options;
            $select.each(function () {
                txt = $(this).children('.' + that.OPTIONS_CLASS + ':selected').text();
                _arr.push(txt);
            })
            return _arr;
        },
        /**
        * 获取联动选择框的数量
        * @return {Number} 选择框的数量
        */
        size: function () {
            return this.$applyTo.size();
        },
        /**
        * 设置选择框的样式
        * @param {Object} style 样式
        * @return {Object} this
        */
        css: function (style) {
            style && this.$applyTo.css(style);
            return this;
        },
        /**
        * 读取数据,并写入到选择框
        * @param {Number} selectIndex 选择框数组的索引值
        * @param {String} parent_id  父级id
        */
        load: function (selectIndex, parent_id, callback) {
            var _that = this;
            //清理index以下的选择框的选项
            for (var i = selectIndex; i < _that.size(); i++) {
                _that.removeOptions(i);
            }
            //存在缓存数据,直接使用缓存数据生成选择框的子项;不存在,则请求数据
            if (_that.cache[parent_id]) {
                _that._create(_that.cache[parent_id], selectIndex);
                _that.$applyTo.eq(selectIndex).trigger("afterLoad");
                if (callback) callback.call(this);
            } else {
                var _ajaxOptions = this.options.ajaxOptions;
                var _d = _ajaxOptions.data;
                var _parentIdField = this.options.field['parent_id'];
                _d[_parentIdField] = parent_id;
                //传递给后台的参数
                _ajaxOptions.data = _d;
                //ajax获取数据成功后的回调函数
                _ajaxOptions.success = function (data) {
                    //遍历数据,获取html字符串
                    if (data.success) {    //2011-6-1 修改
                        var _h = _that._getOptionsHtml(data.data);  //2011-5-31 修改
                        _that._create(_h, selectIndex);
                        _that.cache[parent_id] = _h;
                        _that.$applyTo.eq(selectIndex).trigger("afterLoad.ld");
                        if (callback) callback.call(this);
                    }    
                }
                $.ajax(_ajaxOptions);
            }
        },
        /**
        * 删除指定index索引值的选择框下的选择项
        * @param {Number} index 选择框的索引值
        * @return {Object} this
        */
        removeOptions: function (index) {
            this.$applyTo.eq(index).children("." + this.OPTIONS_CLASS).remove();
            return this;
        },
        selected: function (t, completeCallBack) {
            var _that = this;
            if (t && typeof t == "object" && t.length > 0) {
                var $select = this.$applyTo;
                _load(_that.options.defaultLoadSelectIndex, _that.options.defaultParentId);
            }
            /**
            * 递归获取选择框数据
            * @param {Number} selectIndex 选择框的索引值
            * @param {Number} parent_id   id
            */
            function _load(selectIndex, parent_id) {
                _that.load(selectIndex, parent_id, function () {
                    var id = _selected(selectIndex, t[selectIndex]);
                    selectIndex++;
                    if (selectIndex > _that.size() - 1) {
                        if (completeCallBack) completeCallBack.call(this);
                        return;
                    }
                    _load(selectIndex, id);
                });
            }
            /**
            * 选中包含指定文本的选择项
            * @param {Number} index 选择框的索引值
            * @param {String} text  文本
            * @return {Number} 该选择框的value值
            */
            function _selected(index, text) {
                var id = 0;
                _that.$applyTo.eq(index).children().each(function () {
                    var reg = new RegExp(text);
                    if (reg.test($(this).text())) {
                        $(this).attr("selected", true);
                        id = $(this).val();
                        return;
                    }
                })
                return id;
            }
            return this;
        },
        /**
        * 选择框的值改变后触发的事件
        * @param {Object} e 事件
        */
        onchange: function (e) {
            //实例化后的对象引用
            var _that = e.data.target;
            //选择框的索引值
            var index = e.data.index;
            //目标选择框
            var $target = $(e.target);
            var _parentId = $target.val();
            var _i = index + 1;
            _that.load(_i, _parentId);
        },
        /**
        * 将数据源(json或xml)转成html
        * @param {Object} data
        * @return {String} html代码字符串
        */
        _getOptionsHtml: function (data) {
            var _that = this;
            var ajaxOptions = this.options.ajaxOptions;
            var dataType = ajaxOptions.dataType;
            var field = this.options.field;
            var _h = "";
            _h = _getOptions(data, dataType, field).join(""); ;
            /**
            * 获取选择框项html代码数组
            * @param {Object | Array} data 数据
            * @param {String} dataType 数据类型
            * @param {Object} field 字段
            * @return {Array} aStr 
            */
            function _getOptions(data, dataType, field) {
                var optionClass = _that.OPTIONS_CLASS;
                var aStr = [];
                var id, name;
                if (dataType == "json") {
                    $.each(data, function (i) {
                        id = data[i][field.region_id];
                        name = data[i][field.region_name];
                        var _option = "<option value='" + id + "' class='" + optionClass + "'>" + name + "</option>";
                        aStr.push(_option);

                    })
                } else if (dataType == "xml") {
                    $(data).children().children().each(function () {
                        id = $(this).find(field.region_id).text();
                        name = $(this).find(field.region_name).text();
                        var _option = "<option value='" + id + "' class='" + optionClass + "'>" + name + "</option>";
                        aStr.push(_option);
                    })
                }
                return aStr;
            }
            return _h;
        },
        /**
        * 向选择框添加html
        * @param {String} _h html代码
        * @param {Number} index 选择框的索引值
        */
        _create: function (_h, index) {
            var _that = this;
            this.removeOptions(index);
            this.$applyTo.eq(index).append(_h);
        }
    }
    $.fn.ld.defaults = {
        /**选择框对象数组*/
        selects: null,
        /**ajax配置*/
        ajaxOptions: {
            url: null,
            type: 'get',
            data: {},
            dataType: 'json',
            success: function () { },
            beforeSend: function () { }
        },
        /**默认父级id*/
        defaultParentId: 0,
        /**默认读取数据的选择框*/
        defaultLoadSelectIndex: 0,
        /**默认选择框中的选中项*/
        texts: [],
        /**选择框的样式*/
        style: null,
        /**选择框值改变时的回调函数*/
        change: function () { },
        field: {
            region_id: "CategoryId",
            region_name: "CategoryName",
            parent_id: "CategoryParentID"
        }

    }
})(jQuery);
posted @ 2011-06-04 17:22  曾祥展  阅读(2598)  评论(0编辑  收藏  举报