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Javascript d3.js:如何访问json文件的根节点值?_Javascript_Json_Node.js_D3.js_Hierarchical Data - Fatal编程技术网

Javascript d3.js:如何访问json文件的根节点值?

Javascript d3.js:如何访问json文件的根节点值?,javascript,json,node.js,d3.js,hierarchical-data,Javascript,Json,Node.js,D3.js,Hierarchical Data,我想在json文件中打印根节点的名称,但不确定如何访问它。这是我的json的结构: { "name": "2010", "children": [ { "name" : "White", "children" : [ { "name" : "208", "size" : 2103}, { "name" : "209", "size" : 1846}, { "name" : "228.01", "size" : 2059}, { "name" : "

我想在json文件中打印根节点的名称,但不确定如何访问它。这是我的json的结构:

{
"name": "2010",
"children": [
{
    "name" : "White",
    "children" : [
    { "name" : "208", "size" : 2103},
    { "name" : "209", "size" : 1846},
    { "name" : "228.01", "size" : 2059},
    { "name" : "228.02", "size" : 808},
    { "name" : "228.03", "size" : 1267},
    { "name" : "229.01", "size" : 1302},
    { "name" : "229.02", "size" : 484},
    { "name" : "229.03", "size" : 1045}
    ]
    },
我想用这行代码打印数字2010:

  node.append("text")
  .text(function(d) { if  ( d.parent = null ) {return d.name ; } else { return ("hi") ; };  });

现在,这行代码向我返回Hi,我不知道如何打印2010年。

假设root是保存数据的变量的名称,那么您所要做的就是访问root.name。

.textroot.name,其中root是保存数据的变量的名称。@Larskothoff-这非常有效。非常感谢。