easyui——treegrid级联选中之微改进，解决解除选中的问题。

代码大部分参考网络资源，但针对网络资源中取消选中的各种问题做了改进。

if ($.fn.treegrid) {
    $.extend($.fn.treegrid.methods, {
        /** 
         * 级联选择 
         * @param {Object} target 
         * @param {Object} param  
         *      param包括两个参数: 
         *          id:勾选的节点ID 
         *          deepCascade:是否深度级联 
         * @return {TypeName}  
         */
        cascadeCheck: function (target, param) {
            var opts = $.data(target[0], "treegrid").options;
            if (opts.singleSelect)
                return;
            var idField = opts.idField;//这里的idField其实就是API里方法的id参数  
            var status = false;//用来标记当前节点的状态，true:勾选，false:未勾选  
            var selectNodes = $(target).treegrid('getSelections');//获取当前选中项  
            for (var i = 0; i < selectNodes.length; i++) {
                if (selectNodes[i][idField] == param.id)
                    status = true;
            }

            selectChildren(target[0], param.id, idField, param.deepCascade, status);
            //级联选择父节点
            selectParent(target[0], param.id, idField, status);

            /** 
             * 级联选择父节点 
             * @param {Object} target 
             * @param {Object} id 节点ID 
             * @param {Object} status 节点状态，true:勾选，false:未勾选 
             * @return {TypeName}  
             */
            function selectParent(target, id, idField, status) {
                var parent = $(target).treegrid('getParent', id);
                if (parent) {
                    var parentId = parent[idField];
                    if (status) {
                        $(target).treegrid('select', parentId);
                    } else {
                        var hasChildSelected = false;
                        var selected_hash = {};
                        var selectNodes = $(target).treegrid('getSelections');//获取当前选中项  
                        for (var i = 0; i < selectNodes.length; i++) {
                            selected_hash[selectNodes[i][idField]] = true;
                        }

                        var children = $(target).treegrid('getChildren', parentId);
                        for (var i = 0; i < children.length; i++) {
                            var childID = children[i][idField];
                            if (selected_hash[childID]) hasChildSelected = true;
                        }
                        //同级没有被选中的项
                        if (!hasChildSelected) $(target).treegrid('unselect', parentId);
                    }
                    selectParent(target, parentId, idField, status);
                }
            }
            /** 
             * 级联选择子节点 
             * @param {Object} target 
             * @param {Object} id 节点ID 
             * @param {Object} deepCascade 是否深度级联 
             * @param {Object} status 节点状态，true:勾选，false:未勾选 
             * @return {TypeName}  
             */
            function selectChildren(target, id, idField, deepCascade, status) {
                //深度级联时先展开节点  
                if (!status && deepCascade)
                    $(target).treegrid('expand', id);
                //根据ID获取下层孩子节点  
                var children = $(target).treegrid('getChildren', id);
                for (var i = 0; i < children.length; i++) {
                    var childId = children[i][idField];
                    if (status)
                        $(target).treegrid('select', childId);
                    else
                        $(target).treegrid('unselect', childId);
                    selectChildren(target, childId, idField, deepCascade, status);//递归选择子节点  
                }
            }
        }
    });
}


针对treegrid添加了cascadeCheck方法，其参数是id, deepCascade(bool)。