easyui的datagrid怎么删除当前行数据（数据是从MySQL数据库动态获得的）

script里面的代码：
    $("#tt").datagrid({
                url: 'showAllDept',
                method: 'get',
                fitColumns: true,
                singleSelect: true,
                rownumbers:true,
                columns: [
                    [{
                            field: 'DId',
                            title: '',
                            width: '50px',
                            align: 'center',
                            hidden:true
                        },
                        {
                            field: 'DName',
                            title: '部门名称',
                            width: '500px',
                            align: 'center'
                        },
                        {
                            field: 'operate',
                            title: '操作',
                            align: 'center',
                            width: '440px',
                            formatter: function() {
                                return "<a href='#'>修改</a>&nbsp;&nbsp;&nbsp;&nbsp;" +
                                    "<a href='#' onClick='deleteDept()'>删除</a>";
                            }
                        }
                    ]
                ],

                //显示分页组件，不能设置total
                pagination: true,
                pageSize: 5,
                pageNumber:1,
                pageList: [5, 10, 15]

            });

            //返回datagrid的分页对象
            var $page = $("#tt").datagrid("getPager");

            $page.pagination({
                showPageList: false
            });
        })

        ajax代码：
        function deleteDept(){
            alert("1324");
            $.ajax({
                type:'post',
                url:'deleteDept?DId=' + $("#tt").datagrid('getSelected'),
                dataType:"json",
                success:function(data){
                    if(data.code == 0){
                        alert(data.msg);
                        window.location.href="error.jsp";
                    }else{
                        window.location.href="deptManage.jsp";
                    }
                }

            })
        }

http://blog.csdn.net/a4638966/article/details/55509257