D3.js 是一个基于数据驱动的 JavaScript 库,用于创建动态、交互式的网页可视化。关系图(Graph)是 D3.js 中一种常见的可视化形式,用于展示实体之间的关系。下面是一个简单的 D3.js 关系图 demo 示例,以及相关的基础概念、优势、类型、应用场景和常见问题解答。
以下是一个简单的 D3.js 力导向关系图 demo:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>D3.js Force Directed Graph</title>
<script src="https://d3js.org/d3.v7.min.js"></script>
<style>
.node { stroke: #fff; stroke-width: 1.5px; }
.link { stroke: #999; stroke-opacity: 0.6; }
</style>
</head>
<body>
<svg width="800" height="600"></svg>
<script>
const svg = d3.select("svg");
const width = +svg.attr("width");
const height = +svg.attr("height");
const simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(d => d.id))
.force("charge", d3.forceManyBody())
.force("center", d3.forceCenter(width / 2, height / 2));
const graph = {
nodes: [
{id: "A"},
{id: "B"},
{id: "C"},
{id: "D"}
],
links: [
{source: "A", target: "B"},
{source: "B", target: "C"},
{source: "C", target: "D"},
{source: "D", target: "A"}
]
};
const link = svg.append("g")
.attr("class", "link")
.selectAll("line")
.data(graph.links)
.enter().append("line");
const node = svg.append("g")
.attr("class", "node")
.selectAll("circle")
.data(graph.nodes)
.enter().append("circle")
.attr("r", 10);
node.append("title")
.text(d => d.id);
simulation
.nodes(graph.nodes)
.on("tick", ticked);
simulation.force("link")
.links(graph.links);
function ticked() {
link
.attr("x1", d => d.source.x)
.attr("y1", d => d.source.y)
.attr("x2", d => d.target.x)
.attr("y2", d => d.target.y);
node
.attr("cx", d => d.x)
.attr("cy", d => d.y);
}
</script>
</body>
</html>
d3.forceManyBody()
的强度参数,或尝试不同的布局算法。requestAnimationFrame
控制重绘频率,减少 DOM 操作。通过以上信息,你应该能够理解 D3.js 关系图的基础概念、优势、类型及其应用场景,并能通过示例代码进行实践。如果在实际开发中遇到问题,可以根据常见问题及解决方法进行排查和调整。