Ruby on rails Rails-如何删除散列中的最后一个逗号
我每个人都有一个:Ruby on rails Rails-如何删除散列中的最后一个逗号,ruby-on-rails,geojson,Ruby On Rails,Geojson,我每个人都有一个: { "type": "FeatureCollection", "features": [ <% @pois.each do |poi| %> { "type": "Feature", "geometry": { "type": "Point", "coordinates": [<%= poi.longitude %>, <%= poi.latitude %> ] }, &l
{
"type": "FeatureCollection",
"features": [
<% @pois.each do |poi| %>
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": [<%= poi.longitude %>, <%= poi.latitude %> ]
},
<% end %>
]
}
没关系,我只想删除最后一个逗号;) 我猜想您正在尝试创建/编辑某种类型的JSON对象 不应以这种方式处理JSON对象。 而是使用ActiveModel::Serializer 从
由于您可能对将一个数组转换为另一个数组感兴趣,因此可以使用
map
而不是each
,即
{
"type": "FeatureCollection",
"features":
<% @pois.map do |poi| %>
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": [<%= poi.longitude %>, <%= poi.latitude %> ]
}
}
<% end %>
}
{
“类型”:“FeatureCollection”,
“特点”:
{
“类型”:“功能”,
“几何学”:{
“类型”:“点”,
“坐标”:[,]
}
}
}
这是散列吗?那是什么?那在哪里?你为什么要这么做?这是一个Geojson;)@你可以编译一个包含这些细节的字符串数组,然后用“,”连接数组。然后将没有尾随逗号。
user = User.find(1)
user.as_json
# => { "id" => 1, "name" => "Konata Izumi", "age" => 16,
# "created_at" => "2006/08/01", "awesome" => true}
ActiveRecord::Base.include_root_in_json = true
user.as_json
# => { "user" => { "id" => 1, "name" => "Konata Izumi", "age" => 16,
# "created_at" => "2006/08/01", "awesome" => true } }
{
"type": "FeatureCollection",
"features":
<% @pois.map do |poi| %>
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": [<%= poi.longitude %>, <%= poi.latitude %> ]
}
}
<% end %>
}