Echarts 动态折线图

<script src="http://echarts.baidu.com/build/dist/echarts-all.js"></script>
<script src="http://resource.xiaoyou-game.com/static/public/scripts/jquery-1.8.0.min.js"></script>
<script type="text/javascript">

    var myChart = echarts.init(document.getElementById('main')); 

    function refresh(){

        var orderid = $('#orderid').val();
        var machineid = $('#machineid').val();
        var date = $('#date').val();
        //alert($('#orderid').val());
        $.ajax({
                type: "post",
                url: "http://ccc.com/bbb/aaa",
                dataType: "json",
                data:{'orderid':orderid,'machineid':machineid,'date':date},
                success: function (data) {

                    var hour = data.hour;
                    var usercount = data.usercount;

                    var option = {
                        toolbox: {
                            show : true,
                            feature : {
                                mark : {show: true},
                                dataView : {show: true, readOnly: false},
                                magicType : {show: true, type: ['line','bar']},
                                restore : {show: true},
                                saveAsImage : {show: true}
                            }
                        },
                        tooltip: {
                            show: true
                        },
                        legend: {
                            data:['用户数量']
                        },
                        xAxis : [
                            {
                                type : 'category',
                                data : hour
                            }
                        ],
                        yAxis : [
                            {
                                type : 'value'
                            }
                        ],
                        series : [
                            {
                                "name":"用户数量",
                                "type":"line",
                                "data":usercount,
                                itemStyle: {
                                    normal: {
                                        label : {
                                            show: true,
                                            position:"top"
                                        }
                                    }
                                }
                            }
                        ]
                    };

                    // 为echarts对象加载数据
                    myChart.setOption(option); 

                },
                error: function (XMLHttpRequest, textStatus, errorThrown) {
                    alert(errorThrown);
                }
            });
        }
        // 基于准备好的dom，初始化echarts图表
    </script>