我正在使用D3进行网络爬虫可视化，D3使用基于强制的标记图，如图所示：基于强制的标签放置图
我无法使两个父节点具有相同的公共子节点。使用此图是否不可能？因为示例案例显示了这样一个场景，其中两个节点共享同一个子节点。我该怎么做？我在网页上使用以下脚本来填充和显示图形（脚本中显示的数组只是我用于测试的伪数组，但对象的结构与将要处理的实际数据相似）。请帮忙！
注意：如果我确保没有一个节点有多个父节点，那么这个代码就可以正常工作。编辑：在中使用的.category属性在原始QueuedORG数组中可用，我没有在脚本中创建的示例QueuedORG数组中使用过它。这还不重要。
document.addEventListener('DOMContentLoaded', function () {
drawVisual();
});
function drawVisual()
{
var w = 960, h = 500;
//var w = 1024, h = 768;
//var vis = d3.select("#tab_5_contents").append("svg:svg").attr("width", w).attr("height", h);
var vis = d3.select("#forcedLayoutGraph").append("svg:svg").attr("width", w).attr("height", h);
var QueuedORG = [];
//QueuedORG = JSON.parse(localStorage.getItem('storeArray'));
QueuedORG.push({url: "Root", parentURL: "Root", used:0});
QueuedORG.push({url: "a", parentURL: "Root"});
QueuedORG.push({url: "b", parentURL: "Root"});
QueuedORG.push({url: "c", parentURL: "Root"});
QueuedORG.push({url: "d", parentURL: "Root"});
QueuedORG.push({url: "e", parentURL: "a"});
QueuedORG.push({url: "f", parentURL: "a"});
QueuedORG.push({url: "g", parentURL: "a"});
QueuedORG.push({url: "h", parentURL: "a"});
QueuedORG.push({url: "p", parentURL: "b"});
QueuedORG.push({url: "q", parentURL: "b"});
QueuedORG.push({url: "r", parentURL: "b"});
QueuedORG.push({url: "x", parentURL: "c"});
QueuedORG.push({url: "y", parentURL: "x"});
QueuedORG.push({url: "y", parentURL: "c"});
QueuedORG.push({url: "x", parentURL: "a"});
QueuedORG.push({url: "y", parentURL: "b"});
var nodes = [];
var labelAnchors = [];
var labelAnchorLinks = [];
var links = [];
for(var i = 0; i < QueuedORG.length; i++)
{
var nodeExists = 0;
//check to see if a node for the current url has already been created. If yes, do not create a new node
for(var j = 0; j < nodes.length; j++)
{
if(QueuedORG[i].url == nodes[j].label)
nodeExists = 1;
}
if (nodeExists == 0)
{
var urlLabel = QueuedORG[i].url;
//remove 'http://' part
/*urlLabel = urlLabel.split("http://")[1];
if(urlLabel.match("www"))
urlLabel = urlLabel.split("www.")[1];
var rest = urlLabel.split(".")[1];
urlLabel = urlLabel.split(".")[0];*/
var node = {
label : QueuedORG[i].url,
category : QueuedORG[i].category
};
nodes.push(node);
labelAnchors.push({
node : node
});
labelAnchors.push({
node : node
});
}
};
for(var i=0;i<nodes.length; i++)
{
console.log("node i:"+i+nodes[i]+"n");
console.log("labelAnchor i:"+i+labelAnchors[i]+"n");
}
//To create links for connecting nodes
for(var i = 0; i < QueuedORG.length; i++)
{
var srcIndx = 0, tgtIndx = 0;
for(var j = 0; j < nodes.length; j++)
{
if( QueuedORG[i].url == nodes[j].label ) //to find the node number for the current url
{
srcIndx = j;
}
if( QueuedORG[i].parentURL == nodes[j].label ) //to find the node number for the parent url
{
tgtIndx = j;
}
}
//console.log("src:"+srcIndx+" tgt:"+tgtIndx);
//connecting the current url's node to the parent url's node
links.push({
source : srcIndx,
target : tgtIndx,
weight : 1,
});
labelAnchorLinks.push({
source : i * 2,
target : i * 2 + 1,
weight : 1
});
};
var force = d3.layout.force().size([w, h]).nodes(nodes).links(links).gravity(1).charge(-10000).linkStrength(function(x) {
return x.weight * 10 // charge is for inter-node repel, link distance is node-node distance
});
force.linkDistance(function(d) {
return d.weight * 100;
});
force.start();
var force2 = d3.layout.force().nodes(labelAnchors).links(labelAnchorLinks).gravity(0).linkStrength(10).charge(-500).size([w, h]); //charge is for inter-label repel, link distance is node-label distance
force2.linkDistance(function(d) {
return d.weight * 10;
});
force2.start();
var link = vis.selectAll("line.link").data(links).enter().append("svg:line").attr("class", "link").style("stroke", "#CCC");
var colors = {"1": "black", "2": "blue", "3": "red"}; // 1=root node 2=blog nodes 3=.org nodes
var shape = {"1": "diamond", "2": "cross", "3": "circle"};
var node = vis.selectAll("g.node").data(force.nodes()).enter().append("path").attr("class", "node").call(force.drag);
//node.append("circle").attr("r", 5).style("stroke", "#FFF").style("stroke-width", 3).attr("class", function(d) {return "node category"+d.category});
node.attr("d", d3.svg.symbol().type(function(d) {return shape[d.category];})).style("stroke", "#FFF").style("fill", function(d){ return colors[d.category];});
var anchorLink = vis.selectAll("line.anchorLink").data(labelAnchorLinks)//.enter().append("svg:line").attr("class", "anchorLink").style("stroke", "#999");
var anchorNode = vis.selectAll("g.anchorNode").data(force2.nodes()).enter().append("svg:g").attr("class", "anchorNode");
anchorNode.append("svg:circle").attr("r", 0).style("fill", "#FFF");
anchorNode.append("svg:text").text(function(d, i) {
return i % 2 == 0 ? "" : d.node.label
}).style("fill", "#555").style("font-family", "Arial").style("font-size", 12);
var updateLink = function() {
this.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;
});
}
var updateNode = function() {
this.attr("transform", function(d) {
return "translate(" + d.x + "," + d.y + ")";
});
}
force.on("tick", function() {
force2.start();
node.call(updateNode);
anchorNode.each(function(d, i) {
if(i % 2 == 0) {
d.x = d.node.x;
d.y = d.node.y;
} else {
var b = this.childNodes[1].getBBox();
var diffX = d.x - d.node.x;
var diffY = d.y - d.node.y;
var dist = Math.sqrt(diffX * diffX + diffY * diffY);
var shiftX = b.width * (diffX - dist) / (dist * 2);
shiftX = Math.max(-b.width, Math.min(0, shiftX));
var shiftY = 5;
this.childNodes[1].setAttribute("transform", "translate(" + shiftX + "," + shiftY + ")");
}
});
anchorNode.call(updateNode);
link.call(updateLink);
anchorLink.call(updateLink);
});
}
问题在于组装labelAnchorLinks的方式。通过使用索引i*2和i*2+1，假设每个i有两个节点。只有当QueuedORG中的所有内容都表示一个新节点时，这才是真的。
要修复此问题，请使用源节点的索引，而不是i:
labelAnchorLinks.push({
source : srcIndex * 2,
target : srcIndex * 2 + 1,
weight : 1
});