position: function(point, params, dom, rect, size) {//其中point为当前鼠标的位置，size中有两个属性：viewSize和contentSize，分别为外层div和tooltip提示框的大小var x = point[0]; //
            var y = point[1];var viewWidth = size.viewSize[0];var viewHeight = size.viewSize[1];var boxWidth = size.contentSize[0];var boxHeight = size.contentSize[1];var posX = 0; //x坐标位置var posY = 0; //y坐标位置if (x < boxWidth) { //左边放不开posX = 5;} else { //左边放的下posX = x - boxWidth;}if (y < boxHeight) { //上边放不开posY = 5;} else { //上边放得下posY = y - boxHeight;}return [posX, posY];}

option = {title: {text: '折线图堆叠'},tooltip: {trigger: 'axis',position: function(point, params, dom, rect, size) {//其中point为当前鼠标的位置，size中有两个属性：viewSize和contentSize，分别为外层div和tooltip提示框的大小var x = point[0]; //
            var y = point[1];var viewWidth = size.viewSize[0];var viewHeight = size.viewSize[1];var boxWidth = size.contentSize[0];var boxHeight = size.contentSize[1];var posX = 0; //x坐标位置var posY = 0; //y坐标位置if (x < boxWidth) { //左边放不开posX = 5;} else { //左边放的下posX = x - boxWidth;}if (y < boxHeight) { //上边放不开posY = 5;} else { //上边放得下posY = y - boxHeight;}return [posX, posY];}},legend: {data: ['邮件营销', '联盟广告', '视频广告', '直接访问', '搜索引擎']},grid: {left: '3%',right: '4%',bottom: '3%',containLabel: true},toolbox: {feature: {saveAsImage: {}}},xAxis: {type: 'category',boundaryGap: false,data: ['周一', '周二', '周三', '周四', '周五', '周六', '周日']},yAxis: {type: 'value'},series: [{name: '邮件营销',type: 'line',stack: '总量',data: [120, 132, 101, 134, 90, 230, 210]},{name: '联盟广告',type: 'line',stack: '总量',data: [220, 182, 191, 234, 290, 330, 310]},{name: '视频广告',type: 'line',stack: '总量',data: [150, 232, 201, 154, 190, 330, 410]},{name: '直接访问',type: 'line',stack: '总量',data: [320, 332, 301, 334, 390, 330, 320]},{name: '搜索引擎',type: 'line',stack: '总量',data: [820, 932, 901, 934, 1290, 1330, 1320]}]
};