我有这个 JSON 数据结构:
[
{ "dep": "d1", "name": "name1", "size": "size1" },
{ "dep": "d1", "name": "name2", "size": "size2" },
{ "dep": "d2", "name": "name1", "size": "size3" },
{ "dep": "d2", "name": "name1", "size": "size4" }
]
我想将它转换成这样的嵌套结构:
{
"name": "root",
"children": [
{ "name": "d1",
"children": [
{ "dep": "d1", "name": "name1", "size": "size1" },
{ "dep": "d1", "name": "name2", "size": "size2" }
]
},
{ "name": "d2",
"children": [
{ "dep": "d2", "name": "name1", "size": "size3" },
{ "dep": "d2", "name": "name2", "size": "size4" }
]
}
]
}
... 并进一步使用它来制作 Reingold–Tilford Tree .谁能指出我正确的方向,我是 D3 的新手!
最佳答案
该策略是根据您的需要创建一个新的空数据结构,然后通过遍历整个原始数据集来填充它。这是代码:
var data = [
{ "dep": "d1", "name": "name1", "size": "size1" },
{ "dep": "d1", "name": "name2", "size": "size2" },
{ "dep": "d2", "name": "name1", "size": "size3" },
{ "dep": "d2", "name": "name2", "size": "size4" }
]
var newData = {"name": "root", "children": {}}
data.forEach(function (d) {
if (typeof newData.children[d.dep] !== 'undefined') {
newData.children[d.dep].children.push(d)
} else {
newData.children[d.dep] = {"name": d.dep, "children": [d]}
}
})
newData.children = Object.keys(newData.children).map(function (key) {
return newData.children[key];
});
最后的赋值是将对象转化为数组。
这为 newData
提供了所需的结果:
{
"name": "root",
"children": [
{ "name": "d1",
"children": [
{ "dep": "d1", "name": "name1", "size": "size1" },
{ "dep": "d1", "name": "name2", "size": "size2" }
]
},
{ "name": "d2",
"children": [
{ "dep": "d2", "name": "name1", "size": "size3" },
{ "dep": "d2", "name": "name2", "size": "size4" }
]
}
]
}
jsFiddle: http://jsfiddle.net/chrisJamesC/eB4jF/
注意:此方法不适用于嵌套结构。对于嵌套结构执行此操作会更难,但您始终可以使用递归函数。
编辑:正如@imarane 在他的回答中所建议的,您可以使用 d3.nest()这比我手工制作的解决方案要好得多。因此,您可能会接受他的回答。通过使用它,甚至可以很容易地拥有多层嵌套:
var data = [
{ "dep": "d1", "name": "name1", "size": "size1" },
{ "dep": "d1", "name": "name2", "size": "size2" },
{ "dep": "d2", "name": "name1"},
{ "dep": "d2"}
]
var newData = {
"key":"root",
"children":
d3.nest()
.key(function(d){return d.dep})
.key(function(d){return d.name})
.key(function(d){return d.size})
.entries(data)
}
哪个给:
{"key":"root","children":[
{"key":"d1","values":[
{"key":"name2","values":[
{"dep":"d1","name":"name2","size":"size1"},
{"dep":"d1","name":"name2","size":"size2"}
]}
]},
{"key":"d2","values":[
{"key":"name1","values":[
{"dep":"d2","name":"name1"}
]},
{"key":"undefined","values":[
{"dep":"d2"}
]}
]}
]}
下面是哪个数据结构(希望能更好的理解整点):
var data = [
{ "dep": "d1", "name": "name2", "size": "size1" },
{ "dep": "d1", "name": "name2", "size": "size2" },
{ "dep": "d2", "name": "name1"},
{ "dep": "d2"}
]
JsFiddle: http://jsfiddle.net/chrisJamesC/eB4jF/2/
有关 Nest 的更多信息: http://bl.ocks.org/phoebebright/raw/3176159/
关于javascript - D3 JSON数据转换,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/15912966/