我正在使用 D3 并制作力导向图。我想清除并重新加载图表以响应按钮的点击。但是，当我重新加载已加载的图表时，该图表的格式不正确。这是我正在使用的代码:
<!DOCTYPE html>
<meta charset="utf-8">
<script src="http://d3js.org/d3.v2.js?2.9.1"></script>
<style>
.link {
fill: none;
stroke: #666;
stroke-width: 1.5px;
}
.node circle {
fill: #ccc;
stroke: #fff;
stroke-width: 1.5px;
}
text {
font: 10px sans-serif;
pointer-events: none;
}
</style>
<body>
<script>
var all = [
{source: "Tockwotton", target: "List", type: "woodworking"},
{source: "Tockwotton", target: "Prince Lab", type: "woodworking"},
{source: "Prince Lab", target: "Prince Lab", type: "metalworking"},
{source: "Tockwotton", target: "List", type: "cnc"},
{source: "Granoff", target: "Prince Lab", type: "3d-printing"},
{source: "Tockwotton", target: "List", type: "drafting"},
{source: "List", target: "Prince Lab", type: "welding"},
{source: "Prince Lab", target: "Prince Lab", type: "sand-blaster"},
{source: "Tockwotton", target: "List", type: "finishing"},
{source: "Tockwotton", target: "Prince Lab", type: "finishing"},
{source: "Tockwotton", target: "Tockwotton", type: "laser-cutter"}
];
var wood = [
{source: "Tockwotton", target: "List", type: "woodworking"},
{source: "Tockwotton", target: "Prince Lab", type: "woodworking"}
];
var metal = [
{source: "Prince Lab", target: "Prince Lab", type: "metalworking"}
];
var cnc = [
{source: "Tockwotton", target: "List", type: "cnc"}
];
var print = [
{source: "Granoff", target: "Prince Lab", type: "3d-printing"}
];
var draft = [
{source: "Tockwotton", target: "List", type: "drafting"}
];
var weld = [
{source: "List", target: "Prince Lab", type: "welding"}
];
var sand = [
{source: "Prince Lab", target: "Prince Lab", type: "sand-blaster"}
];
var finishing = [
{source: "Tockwotton", target: "List", type: "finishing"},
{source: "Tockwotton", target: "Prince Lab", type: "finishing"}
];
var laser = [
{source: "Tockwotton", target: "Tockwotton", type: "laser-cutter"}
];
function render(linkdata){
d3.selectAll("svg").remove();
links = linkdata;
nodes = {};
// Compute the distinct nodes from the links.
links.forEach(function(link) {
link.source = nodes[link.source] || (nodes[link.source] = {name: link.source, type: link.type});
link.target = nodes[link.target] || (nodes[link.target] = {name: link.target, type: link.type});
});
width = 960,
height = 500;
force = d3.layout.force()
.nodes(d3.values(nodes))
.links(links)
.size([width, height])
.linkDistance(60)
.charge(-300)
.on("tick", tick)
.start();
svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);
link = svg.selectAll(".link")
.data(force.links())
.enter().append("line")
.attr("class", "link");
node = svg.selectAll(".node")
.data(force.nodes())
.enter().append("g")
.attr("class", "node")
.on("mouseover", mouseover)
.on("mouseout", mouseout)
.call(force.drag);
node.append("circle")
.attr("r", 8);
node.append("text")
.attr("x", 12)
.attr("dy", ".35em")
.text(function(d) { return d.name; });
function tick() {
link
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node
.attr("transform", function(d) { return "translate(" + d.x + "," + d.y + ")"; });
}
function mouseover() {
d3.select(this).select("circle").transition()
.duration(750)
.attr("r", 16);
}
function mouseout() {
d3.select(this).select("circle").transition()
.duration(750)
.attr("r", 8);
}
}
</script>
<div id="nav">
<div id="wood">
<a onclick="render(wood)">Woodworking</a>
</div>
<div id="metal">
<a onclick="render(metal)">Metalworking</a>
</div>
<div id="cnc">
<a onclick="render(cnc)">CNC</a>
</div>
<div id="print">
<a onclick="render(print)">3D Printing</a>
</div>
<div id="draft">
<a onclick="render(draft)">Drafting</a>
</div>
<div id="weld">
<a onclick="render(weld)">Welding</a>
</div>
<div id="sand">
<a onclick="render(sand)">Sand Blast</a>
</div>
<div id="finishing">
<a onclick="render(finishing)">Finishing</a>
</div>
<div id="laser">
<a onclick="render(laser)">Laser Cutting</a>
</div>
<div id="all">
<a onclick="render(all)">All</a>
</div>
</div>
</body>
Try it请注意，第一次单击某个项目时，它工作正常，但如果再次单击它，您只会获得一个名为 [object Object] 的节点。这是为什么？我该如何解决这个问题？
最佳答案
当您使用links = linkdata时，它可能不会执行您期望的操作。与其他一些语言一样，这不会复制数据；而是复制数据。相反，它只是使 links 指向 linkdata 指向的同一位置。当您循环遍历链接并将它们修改为彼此指向时，您正在修改数组中的原始对象。当您再次循环它们时，它们已经被修改，导致您遇到不良行为。
为了避免这种命运，您需要在修改数组之前对其进行深度复制。有quite a few ways to do that ，但您需要确保您使用的任何解决方案都会将数组克隆为数组，而不会将其转换为普通的对象。
关于javascript - 图表无法正确重新加载到 D3 强制布局中，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/17690703/