$geoWithin

Definition定义

$geoWithin

Selects documents with geospatial data that exists entirely within a specified shape.选择包含完全存在于指定形状中的地理空间数据的文档。

The specified shape can be either a GeoJSON Polygon(either single-ringed or multi-ringed), a GeoJSON MultiPolygon, or a shape defined by legacy coordinate pairs. 指定的形状可以是GeoJSON多边形（单环或多环）、GeoJSON多重多边形或由传统坐标对定义的形状。The $geoWithin operator uses the $geometry operator to specify the GeoJSON object.$geoWithin运算符使用$geometry运算符指定GeoJSON对象。

To specify a GeoJSON polygons or multipolygons using the default coordinate reference system (CRS), use the following syntax:要使用默认坐标参考系（CRS）指定GeoJSON多边形或多多边形，请使用以下语法：

{
   <location field>: {
      $geoWithin: {
         $geometry: {
            type: <"Polygon" or "MultiPolygon"> ,
            coordinates: [ <coordinates> ]
         }
      }
   }
}

For $geoWithin queries that specify GeoJSON geometries with areas greater than a single hemisphere, the use of the default CRS results in queries for the complementary geometries.对于指定面积大于单个半球的GeoJSON几何图形的$geoWithin查询，使用默认CRS会导致查询互补几何图形。

To specify a single-ringed GeoJSON polygon with a custom MongoDB CRS, use the following prototype that specifies the custom MongoDB CRS in the $geometry expression:要使用自定义MongoDB CRS指定单个环形GeoJSON多边形，请使用以下原型在$geometry表达式中指定自定义MongoDBCRS：

{
   <location field>: {
      $geoWithin: {
         $geometry: {
           type: "Polygon" ,
           coordinates: [ <coordinates> ],
           crs: {
              type: "name",
              properties: { name: "urn:x-mongodb:crs:strictwinding:EPSG:4326" }
           }
         }
      }
   }
}

The custom MongoDB CRS uses a counter-clockwise winding order and allows $geoWithin to support queries with a single-ringed GeoJSON polygon whose area is greater than or equal to a single hemisphere. 自定义MongoDB CRS使用逆时针缠绕顺序，并允许$geoWithin支持使用面积大于或等于单个半球的单个环形GeoJSON多边形进行查询。If the specified polygon is smaller than a single hemisphere, the behavior of $geoWithin with the MongoDB CRS is the same as with the default CRS. 如果指定的多边形小于单个半球，则$geoWithin与MongoDB CRS的行为与默认CRS的相同。See also "Big" Polygons.请参见“大”多边形。

If querying for inclusion in a shape defined by legacy coordinate pairs on a plane, use the following syntax:如果查询是否包含在由平面上的旧坐标对定义的形状中，请使用以下语法：

{
   <location field>: {
      $geoWithin: { <shape operator>: <coordinates> }
   }
}

The available shape operators are:可用的形状运算符有：

• $box,
• $polygon,
• $center (defines a circle), and（定义圆），以及
• $centerSphere (defines a circle on a sphere).（定义球体上的圆）。

Important重要

If you use longitude and latitude, specify coordinates in order of longitude, latitude.如果使用经度和纬度，请按longitude, latitude的顺序指定坐标。

Behavior行为

Examples示例

db.places.find(
   {
     loc: {
       $geoWithin: {
          $geometry: {
             type : "Polygon" ,
             coordinates: [ [ [ 0, 0 ], [ 3, 6 ], [ 6, 1 ], [ 0, 0 ] ] ]
          }
       }
     }
   }
)

db.places.find(
   {
     loc: {
       $geoWithin: {
          $geometry: {
             type : "Polygon" ,
             coordinates: [
               [
                 [ -100, 60 ], [ -100, 0 ], [ -100, -60 ], [ 100, -60 ], [ 100, 60 ], [ -100, 60 ]
               ]
             ],
             crs: {
                type: "name",
                properties: { name: "urn:x-mongodb:crs:strictwinding:EPSG:4326" }
             }
          }
       }
     }
   }
)