option = {
    title: {
        text: '簡單網路拓撲'
    },
    tooltip: {},
    animationDurationUpdate: 1500,
    animationEasingUpdate: 'quinticInOut',
    series : [
        {
            type: 'graph',
            layout: 'none',
            symbolSize: 50,
            roam: true,
            label:
 
 {
                normal: {
                    show: true
                }
            },
            edgeSymbol: ['circle', 'arrow'],
            edgeSymbolSize: [4, 10],
            edgeLabel: {
                normal: {
                    textStyle: {
                        fontSize: 20
                    }
 

                }
            },
            data: [{
                name: '伺服器1',
                x: 100,
                y: 100
            }, {
                name: '伺服器2',
                x: 220,
                y: 310
            }, {
                name: '路由器',
                x: 100,
                y:
 
 200
            }, {
                name: '伺服器4',
                x: 10,
                y: 300
            }],
            // links: [],
            links: [{
                source: '路由器',
                target: '伺服器1'
            }, {
                source: '路由器',
                target: '伺服器2'
            }, {
                source: '路由器',
                target: '伺服器4'
            }],
            lineStyle: {
                normal: {
                    opacity: 0.9,
                    width: 2,
                    curveness: 0
                }
            }
        }
    ]
};