Query a feature layer (spatial)

Learn how to execute a spatial query to access polygon featuresA feature is a single record, also known as a row, that represents a real-world entity. It typically contains a geometry (point, multipoint, polyline, or polygon) and attributes but it can also contain just attributes.Learn more from a feature serviceA feature service is a data service that provides access to spatial and non-spatial data in feature layers, feature layer views, and tables.Learn more.

A feature layerA feature layer (server-side) is a spatially-enabled table in a feature service. All features in a feature layer share the same geometry type and set of fields.Learn more can contain a large number of featuresA feature is a single record, also known as a row, that represents a real-world entity. It typically contains a geometry (point, multipoint, polyline, or polygon) and attributes but it can also contain just attributes.Learn more stored in ArcGISArcGIS is the brand name for all of the desktop, server, and developer products and technologies offered by Esri.Learn more. To access a subset of these features, you can execute an SQL or spatial query, either together or individually. The results can contain the attributesAttributes are fields and values for a single feature or non-spatial record. They are typically stored in a database or service such as a feature service.Learn more, geometryA geometry is a geometric shape, such as a point, polyline, or polygon, that contains one or more coordinates and a spatial reference.Learn more, or both for each record. SQL and spatial queries are useful when a feature layer is very large and you want to access only a subset of its data.

In this tutorial, you sketch a featureA feature is a single record, also known as a row, that represents a real-world entity. It typically contains a geometry (point, multipoint, polyline, or polygon) and attributes but it can also contain just attributes.Learn more on the map and use ArcGIS REST JS to perform a spatial query against the LA County Parcels hosted feature layerA hosted feature layer is a hosted layer (item) in a portal that is used to manage the properties and settings of a spatially-enabled feature layer in a feature service.Learn more. The layer contains ±2.4 million features. The spatial query returns all of the parcels that intersect the sketched feature. A pop-up is also used to display feature attributes.

Prerequisites

Steps

Get the starter app

Select a type of authentication and follow the steps to create a new app.

Set up authentication

Set developer credentials

Use the API key or OAuth developer credentialsDeveloper credentials are a type of item in a portal that contains parameters for authentication. There are two types of developer credentials: API key credentials and OAuth credentials.Learn more so your application can access ArcGIS servicesA service, also known as an ArcGIS service, is software that supports an ArcGIS REST API and provides geospatial functionality or data. A service can be hosted by Esri or in ArcGIS Enterprise.Learn more.

Add script references

In addition to Leaflet and Esri Leaflet, reference the Leaflet Geoman plugin. The plugin allows you to create pointA point is a type of geometry containing a single set of x,y coordinates and a spatial reference.Learn more, lineA polyline is a type of geometry containing ordered point coordinates and a spatial reference.Learn more, and polygonA polygon is a type of geometry containing an array of rings and a spatial reference. Each ring contains an array of point coordinates, where the first and last point are the same.Learn more graphics on the map.

1. Add <script> and <link> tags to reference the libraries.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
       <!-- Load Leaflet from CDN -->
       <link rel="stylesheet" href="https://unpkg.com/leaflet@1.9.4/dist/leaflet.css" crossorigin="">
       <script src="https://unpkg.com/leaflet@1.9.4/dist/leaflet.js" crossorigin=""></script>
   
       <!-- Load Esri Leaflet from CDN -->
       <script src="https://unpkg.com/esri-leaflet@3.0.19/dist/esri-leaflet.js"></script>
       <script src="https://unpkg.com/esri-leaflet-vector@4.3.2/dist/esri-leaflet-vector.js"></script>
   
       <!-- Load Leaflet Geoman from CDN -->
       <link rel="stylesheet" href="https://unpkg.com/@geoman-io/leaflet-geoman-free@latest/dist/leaflet-geoman.css">
       <script src="https://unpkg.com/@geoman-io/leaflet-geoman-free@latest/dist/leaflet-geoman.min.js"></script>
   

   Expand

Add the parcels layer

Use the FeatureLayer class to perform a query against the LA County Parcels feature layerA feature layer (client-side) is a data layer that can access and display features from a feature service that has the same type of geometry and attribute fields.Learn more. Since you are performing a server-side query, you can hide the features.

1. Create a FeatureLayer object with the LA County Parcels hosted feature layer as its source.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
         L.esri.Vector.vectorBasemapLayer(basemapEnum, {
           token: accessToken
         }).addTo(map);
   
         var parcels = L.esri
           .featureLayer({
             url: "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/LA_County_Parcels/FeatureServer/0",
             simplifyFactor: 0.5,
             precision: 4,
   
           })
           .addTo(map);
   

   Expand

2. Hide all features in the layer using a layer definitionA layer definition is a SQL WHERE clause for a feature layer that is used to select a subset of features from a feature service.Learn more.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
         var parcels = L.esri
           .featureLayer({
             url: "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/LA_County_Parcels/FeatureServer/0",
             simplifyFactor: 0.5,
             precision: 4,
   
             where: "1 = 0" // Hide the feature layer until queried
   
           })
           .addTo(map);
   

   Expand

Set up the Geoman toolbar

You can use the Leaflet Geoman toolbar to create point, line, and polygon geometries via a user interface.

1. Add map.pm.addControls to create the Geoman toolbar. Hide all buttons except for drawMarker, drawPolyline, and drawPolygon.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
         var parcels = L.esri
           .featureLayer({
             url: "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/LA_County_Parcels/FeatureServer/0",
             simplifyFactor: 0.5,
             precision: 4,
   
             where: "1 = 0" // Hide the feature layer until queried
   
           })
           .addTo(map);
   
         map.pm.addControls({
           position: "topleft",
           // Customize the visible tools
           editControls: false,
           drawRectangle: false,
           drawCircle: false,
           drawCircleMarker: false,
           drawText: false
         });
   
   

   Expand

2. Set map.pm.setGlobalOptions to define the style properties for the drawn geometries.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
         map.pm.addControls({
           position: "topleft",
           // Customize the visible tools
           editControls: false,
           drawRectangle: false,
           drawCircle: false,
           drawCircleMarker: false,
           drawText: false
         });
   
         map.pm.setGlobalOptions({
           pathOptions: {
             weight: 2,
             color: "#4d4d4d",
             fillColor: "#808080",
             fillOpacity: 0.2,
             dashArray: [4, 4]
           }
         });
   

   Expand

3. Click Run at the top right to test your code. You should be able to sketch a point, line, or polygon.

Get the drawn feature

Leaflet Geoman emits a pm:create event when you have finished sketching a feature. You can listen to this event to respond to the newly created feature.

1. Add an event handler for the pm:create event. Format its output to access the new layer object.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
         map.pm.setGlobalOptions({
           pathOptions: {
             weight: 2,
             color: "#4d4d4d",
             fillColor: "#808080",
             fillOpacity: 0.2,
             dashArray: [4, 4]
           }
         });
   
         map.on("pm:create", ({ layer }) => {
   
         });
   

   Expand

2. Remove the previousLayer with the remove method. Set previousLayer to the newly drawn layer.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
         var previousLayer;
   
         map.on("pm:create", ({ layer }) => {
   
           if (previousLayer) {
             previousLayer.remove();
           }
           previousLayer = layer;
   
         });
   

   Expand

Run the query

Use the FeatureLayer.query method to find features in the LA County Parcels feature layer that intersect the sketched geometry.

1. Convert the sketched feature into GeoJSON to access its geometry. Create a query on the parcels layer that returns all parcels intersecting the sketched geometry.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
         var previousLayer;
   
         map.on("pm:create", ({ layer }) => {
   
           if (previousLayer) {
             previousLayer.remove();
           }
           previousLayer = layer;
   
           var feature = layer.toGeoJSON();
           parcels
             .query()
             .intersects(feature.geometry)
             .limit(2000)
   
         });
   

   Expand

2. Return the feature ids. Display the results with the setWhere method.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
           var feature = layer.toGeoJSON();
           parcels
             .query()
             .intersects(feature.geometry)
             .limit(2000)
   
             .ids(function (error, queryResult) {
               parcels.setWhere("OBJECTID IN (" + queryResult.join(",") + ")");
             });
   

   Expand

3. Create a pop-up using bindPopup. Set its contents dynamically based on the currently clicked feature.

   Expand

   Use dark colors for code blocks

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
   100
   101
   102
   103
   104
   105
   106
   107
   108
   109
   110
   111
   112
   113
   114
   115
   116
   117
   118
   119
   120
   121
   122
   123
   124
   125
   126
   127
   128
   129
   130
           var feature = layer.toGeoJSON();
           parcels
             .query()
             .intersects(feature.geometry)
             .limit(2000)
   
             .ids(function (error, queryResult) {
               parcels.setWhere("OBJECTID IN (" + queryResult.join(",") + ")");
             });
   
         });
   
         parcels.bindPopup(function (layer) {
           return L.Util.template("<b>Parcel {APN}</b>" + "Type: {UseType} <br>" + "Tax Rate City: {TaxRateCity}", layer.feature.properties);
         });
   

   Expand

Run the app

Run the app.

When you click on the map to draw a polygonA polygon is a type of geometry containing an array of rings and a spatial reference. Each ring contains an array of point coordinates, where the first and last point are the same.Learn more, a spatial query will run against the feature layerA feature layer (client-side) is a data layer that can access and display features from a feature service that has the same type of geometry and attribute fields.Learn more and display all land parcels that intersect the boundary of the featureA feature is a single record, also known as a row, that represents a real-world entity. It typically contains a geometry (point, multipoint, polyline, or polygon) and attributes but it can also contain just attributes.Learn more. You can click on a parcel to see a pop-up with information about the parcel.

What's next?

Learn how to use additional location services in these tutorials: