使用dagre-d3做一个dag图（关系图）

dagre-d3插件github地址：https://github.com/dagrejs/dagre-d3

简易版github网址: https://github.com/xuhuihui/svg/tree/master/demo/demo2

csdn引入:

index.html

index.js

1.声明数组state（点）和edg（边）

 var state = [
    { label: 'project_etl_start\n虚节点', class: 'type-suss' }, 
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },   
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },  
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },  
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },   
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },    
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },    
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },    
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },    
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },    
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },    
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },    
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },    
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' },    
    { label: 'project_etl_start\n虚节点', class: 'type-TOP' }
]  
var edg = [
    { start: 1, end: 4, option: {} },
    { start: 1, end: 3, option: {} },
    { start: 1, end: 2, option: {} },
    { start: 6, end: 7, option: {} },
    { start: 5, end: 6, option: {} },
    { start: 9, end: 10, option: {} },
    { start: 8, end: 9, option: {} },
    { start: 11, end: 12, option: {} }, 
    { start: 8, end: 11, option: {} },
    { start: 5, end: 8, option: {} },
    { start: 1, end: 5, option: {} },
    { start: 13, end: 14, option: {} },
    { start: 1, end: 13, option: {} },
    { start: 0, end: 1, option: {} }
  ]

2.创建对象graph。

  var g = new dagreD3.graphlib.Graph()
        .setGraph({})
        .setDefaultEdgeLabel(function () { return {}; });

3.声明并添加树节点和边。

  for (let i in state) { //画点
    let el = state[i]
    g.setNode(i, {
      id: i,
      label: el.label,
      class: el.class
    });
  }
  for (let i in edg) { // 画连线
    let el = edg[i]
    g.setEdge(el.start, el.end, {
      style: "stroke: #0fb2cc; fill: none;",
      arrowheadStyle: "fill: #0fb2cc;stroke: #0fb2cc;",
      arrowhead: 'vee'
    });
  }

4.渲染dag图。

   var render = new dagreD3.render();
    var svg = d3.select("#svgCanvas"); //声明节点
    svg.select("g").remove(); //删除以前的节点，清空画面
    var svgGroup = svg.append("g");
    var inner = svg.select("g");
    var zoom = d3.zoom().on("zoom", function () { //添加鼠标滚轮放大缩小事件
      inner.attr("transform", d3.event.transform);
    });
    svg.call(zoom);
    this.drawNode();//画点
    this.drawEdg();// 画连线
    render(d3.select("svg g"), this.g); //渲染节点
    let max = svg._groups[0][0].clientWidth>svg._groups[0][0].clientHeight?svg._groups[0][0].clientWidth:svg._groups[0][0].clientHeight;
    var initialScale = max/779; //initialScale元素放大倍数，随着父元素宽高发生变化时改变初始渲染大小
    var tWidth = (svg._groups[0][0].clientWidth  - this.g.graph().width * initialScale) / 2; //水平居中
    var tHeight = (svg._groups[0][0].clientHeight  - this.g.graph().height * initialScale) / 2; //垂直居中
    svg.call(zoom.transform, d3.zoomIdentity.translate(tWidth, tHeight).scale(initialScale)); //元素水平垂直居中

5.添加鼠标右键事件，样式如图：

  //主要代码如下：
  var svgCanvas = document.getElementById('svg-canvas'); //svg
  var myMenu = document.getElementById("myMenu"); //右键菜单

  svgCanvas.addEventListener('mouseover', function (e) {//监听鼠标右键
    e.preventDefault();
    if (e.target.tagName === 'rect') {
          myMenu.style.top = event.clientY + "px"; //获取鼠标位置
          myMenu.style.left = event.clientX + "px";
          myMenu.style.display = 'block';      //显示相应右键内容
    }
  })
  document.addEventListener("click", (event) => {
     myMenu.style.display = 'none';
  });