尽管阅读了其他人就此事发布的大量问题和答案,但我在将 id 分配给外部坐标 json
文件中的路径时遇到了问题。文件中的数据如下所示(它也在我的 html header 中引用,见下文):
var neighborhoods_json = {
"type": "FeatureCollection",
"features": [
{ "type": "Feature", "properties": { "Name": "Roslindale", "density": 5.5800 }, "geometry": { "type": "MultiPolygon", "coordinates": [ [ [ [ -71.1259, 42.2720 ], [ -71.1257, 42.2723 ], [ -71.1256, 42.2724 ], [ -71.1255, 42.2725 ],....
我看到其他人问过同样的问题,答案是添加此行来为每个路径创建 id:
.attr("id", function(d) {return d.id;})
但是我的 json
数据不包含 id
,所以我想我应该使用 Name
来代替:
.attr("id", function(d) {return d.Name;})
然后,我尝试使用 Name
作为 id
选择创建的路径之一。我们的想法是简单地选择其中一条路径,然后将其填充颜色更改为红色。但我要么没有正确分配 id,要么没有正确选择路径。谁能告诉我我做错了什么?
<script src="http://d3js.org/d3.v3.min.js"></script>
<script src="http://maptimeboston.github.io/d3-maptime/example3/neighborhoods.js"></script>
</head>
<body>
<script>
var width = 700,
height = 580;
var svg = d3.select( "body" )
.append( "svg" )
.attr( "width", width )
.attr( "height", height );
var neighborhoods = svg.append( "g" );
var albersProjection = d3.geo.albers()
.scale( 190000 )
.rotate( [71.057,0] )
.center( [0, 42.313] )
.translate( [width/2,height/2] );
var geoPath = d3.geo.path()
.projection( albersProjection );
neighborhoods.selectAll( "path" )
.data( neighborhoods_json.features )
.enter()
.append("path")
.attr( "d", geoPath)
.attr("id", function(d) {return d.Name;})
.attr("fill", "steelblue");
neighborhoods.select("path#Roslindale")
.attr("fill", "red");
</script>
最佳答案
在 id
函数中,Name
属性嵌套在 properties
属性内
neighborhoods.selectAll( "path" )
.data( neighborhoods_json.features )
.enter()
.append("path")
.attr( "d", geoPath)
.attr("id", function(d) {return d.properties.Name;})
.attr("fill", "steelblue");
关于javascript - D3 : Having trouble selecting a path from json data,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/38626666/