Search for an address

Before starting this tutorial:

• You need an ArcGIS Location Platform or ArcGIS Online account.

• Ensure your development environment meets the system requirements.

Optionally, you may want to install the ArcGIS Maps SDK for .NET to get access to project templates in Visual Studio (Windows only) and offline copies of the NuGet packages.

Option 1: Develop the code

To start the tutorial, complete the Display a map tutorial. This creates a map to display the Santa Monica Mountains in California using the topographic basemap from the ArcGIS Basemap Styles service The ArcGIS Basemap Styles service, also referred to as the Basemap Styles service, is a location service that provides basemap styles and data for the world. It returns styles as Mapbox styles and web maps, and data as vector tiles and/or map tiles. It supports all of the styles in the ArcGIS Basemap style and Open Basemap style family. An ArcGIS Location Platform or ArcGIS Online account is required to use the service. Learn more .

Open a Visual Studio solution

1. Open the Visual Studio solution you created by completing the Display a map tutorial.
2. Continue following the instructions to:
   • Configure authentication in your app so that your app users can access the ArcGIS Geocoding service A geocoding service is a service that can search for addresses, place addresses, businesses, reverse geocode coordinates to addresses, provide suggestions for places, and perform bulk geocoding. It is hosted by Esri as the ArcGIS Geocoding service and can also be hosted in ArcGIS Enterprise. Learn more to find addresses and show their location on the map.
   • Add functionality to search for an address or place using the ArcGIS Geocoding service A geocoding service is a service that can search for addresses, place addresses, businesses, reverse geocode coordinates to addresses, provide suggestions for places, and perform bulk geocoding. It is hosted by Esri as the ArcGIS Geocoding service and can also be hosted in ArcGIS Enterprise. Learn more .

Update the tutorial name used in the project (optional)

The Visual Studio solution, project, and the namespace for all classes currently use the name DisplayAMap. Follow the steps below if you prefer the name to reflect the current tutorial. These steps are not required, your code will still work if you keep the original name.

Set developer credentials

If you implemented API key authentication API key authentication is a type of authentication that uses an API key to authenticate requests to ArcGIS services and secure portal items. Learn more in the Display a map tutorial, the API key access token will only have the Basemaps privilege. The Search for an address tutorial requires the Geocoding privilege to search for an address using the LocatorTask. To create an API Key access token that has the Basemaps and Geocoding privileges, see the Set up authentication step and then follow the instructions below.

Add a graphics overlay

A graphics overlay A graphics overlay is a client-side, temporary container of graphics to display on a map view or scene view. Learn more is a container for graphics A graphic is a visual element composed of a geometry, symbol, and attributes that is displayed on a map or scene. Learn more . Graphics overlays are typically used to display temporary information, such as the results of an address search operation, and are displayed on top of all other layers A layer is a reference to a collection of geographic data that is used to access and display data. The data for layers are typically provided by the basemap layer service and data services. Learn more . They do not persist when you save the map A map is a collection of layers that are displayed in 2D. It is typically composed of a basemap layer and data layers. Learn more .

1. In the Visual Studio > Solution Explorer, double-click MapViewModel.cs to open the file.

   More info

   The project uses the Model-View-ViewModel (MVVM) design pattern to separate the application logic (view model) from the user interface (view). MapViewModel.cs contains the view model class for the application, called MapViewModel. See the Microsoft documentation for more information about the Model-View-ViewModel pattern.

2. Add additional required using statements to your MapViewModel class. Geocoding contains classes used for geocoding (finding geographic locations from an address). The Esri.ArcGISRuntime.UI namespace contains the GraphicsOverlay and Graphic classes and Esri.ArcGISRuntime.Symbology contains the classes that define the symbols for displaying them.

   using System;
   using System.Collections.Generic;
   using Esri.ArcGISRuntime.Geometry;
   using Esri.ArcGISRuntime.Mapping;
   using System.ComponentModel;
   using System.Runtime.CompilerServices;
   
   using Esri.ArcGISRuntime.Symbology;
   using Esri.ArcGISRuntime.Tasks.Geocoding;
   using Esri.ArcGISRuntime.UI;
   using System.Drawing;
   using System.Linq;
   using System.Threading.Tasks;

3. In the view model, create a new property named GraphicsOverlays. This is a collection of GraphicsOverlay that will store geocode result graphics (address location and label).

   45 collapsed lines
   // Copyright 2021 Esri
   // Licensed under the Apache License, Version 2.0 (the "License");
   // you may not use this file except in compliance with the License.
   // You may obtain a copy of the License at
   //
   // https://www.apache.org/licenses/LICENSE-2.0
   //
   // Unless required by applicable law or agreed to in writing, software
   // distributed under the License is distributed on an "AS IS" BASIS,
   // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   // See the License for the specific language governing permissions and
   // limitations under the License.
   
   
   using System;
   using System.Collections.Generic;
   using Esri.ArcGISRuntime.Geometry;
   using Esri.ArcGISRuntime.Mapping;
   using System.ComponentModel;
   using System.Runtime.CompilerServices;
   
   using Esri.ArcGISRuntime.Symbology;
   using Esri.ArcGISRuntime.Tasks.Geocoding;
   using Esri.ArcGISRuntime.UI;
   using System.Drawing;
   using System.Linq;
   using System.Threading.Tasks;
   
   namespace SearchForAnAddress
   {
       class MapViewModel : INotifyPropertyChanged
       {
           public MapViewModel()
           {
               SetupMap();
           }
   
           public event PropertyChangedEventHandler? PropertyChanged;
           protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
           {
               var propertyChangedHandler = PropertyChanged;
               if (propertyChangedHandler != null)
                   propertyChangedHandler(this, new PropertyChangedEventArgs(propertyName));
           }
   
           private Map? _map;
           public Map? Map
           {
               get { return _map; }
               set
               {
                   _map = value;
                   OnPropertyChanged();
               }
           }
   
           private GraphicsOverlayCollection? _graphicsOverlayCollection;
           public GraphicsOverlayCollection? GraphicsOverlays
           {
               get { return _graphicsOverlayCollection; }
               set
               {
                   _graphicsOverlayCollection = value;
                   OnPropertyChanged();
               }
           }
   17 collapsed lines
   
           private void SetupMap()
           {
               // Create a new map with a 'topographic vector' basemap.
               Map map = new Map(BasemapStyle.ArcGISTopographic);
   
               // Set the initial viewpoint around the Santa Monica Mountains in California.
               var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);
               map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);
   
               // Set the view model "Map" property.
               this.Map = map;
   
           }
   
       }
   }

4. At the end of the SetupMap function, add code to create a new GraphicsOverlay, add it to a collection, and assign it to the GraphicsOverlays property.

   76 collapsed lines
   // Copyright 2021 Esri
   // Licensed under the Apache License, Version 2.0 (the "License");
   // you may not use this file except in compliance with the License.
   // You may obtain a copy of the License at
   //
   // https://www.apache.org/licenses/LICENSE-2.0
   //
   // Unless required by applicable law or agreed to in writing, software
   // distributed under the License is distributed on an "AS IS" BASIS,
   // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   // See the License for the specific language governing permissions and
   // limitations under the License.
   
   
   using System;
   using System.Collections.Generic;
   using Esri.ArcGISRuntime.Geometry;
   using Esri.ArcGISRuntime.Mapping;
   using System.ComponentModel;
   using System.Runtime.CompilerServices;
   
   using Esri.ArcGISRuntime.Symbology;
   using Esri.ArcGISRuntime.Tasks.Geocoding;
   using Esri.ArcGISRuntime.UI;
   using System.Drawing;
   using System.Linq;
   using System.Threading.Tasks;
   
   namespace SearchForAnAddress
   {
       class MapViewModel : INotifyPropertyChanged
       {
           public MapViewModel()
           {
               SetupMap();
           }
   
           public event PropertyChangedEventHandler? PropertyChanged;
           protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
           {
               var propertyChangedHandler = PropertyChanged;
               if (propertyChangedHandler != null)
                   propertyChangedHandler(this, new PropertyChangedEventArgs(propertyName));
           }
   
           private Map? _map;
           public Map? Map
           {
               get { return _map; }
               set
               {
                   _map = value;
                   OnPropertyChanged();
               }
           }
   
           private GraphicsOverlayCollection? _graphicsOverlayCollection;
           public GraphicsOverlayCollection? GraphicsOverlays
           {
               get { return _graphicsOverlayCollection; }
               set
               {
                   _graphicsOverlayCollection = value;
                   OnPropertyChanged();
               }
           }
   
           private void SetupMap()
           {
               // Create a new map with a 'topographic vector' basemap.
               Map map = new Map(BasemapStyle.ArcGISTopographic);
   
               // Set the initial viewpoint around the Santa Monica Mountains in California.
               var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);
               map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);
   
               // Set the view model "Map" property.
               this.Map = map;
   
               // Set the view model "GraphicsOverlays" property.
               GraphicsOverlay overlay = new GraphicsOverlay();
               GraphicsOverlayCollection overlayCollection = new GraphicsOverlayCollection
               {
                   overlay
               };
               this.GraphicsOverlays = overlayCollection;
   
           }
   3 collapsed lines
   
       }
   }

5. In the Visual Studio > Solution Explorer, double-click MainWindow.xaml to open the file.

6. Use data binding to bind the GraphicsOverlays property of the MapViewModel to the MapView control.

   Data binding and MVVM

   Data binding and the Model-View-ViewModel (MVVM) design pattern allow you to separate the logic in your app (the view model) from the presentation layer (the view). Graphics can be added and removed from the graphics overlays in the view model, and those changes appear in the map view through data binding.

   15 collapsed lines
   <Window x:Class="SearchForAnAddress.MainWindow"
           xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
           xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
           xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
           xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
           xmlns:local="clr-namespace:SearchForAnAddress"
           xmlns:esri="http://schemas.esri.com/arcgis/runtime/2013"
           mc:Ignorable="d"
           Title="MainWindow" Height="450" Width="800">
       <Window.Resources>
           <local:MapViewModel x:Key="MapViewModel" />
       </Window.Resources>
   
       <Grid>
   
           <esri:MapView x:Name="MainMapView"
                         Map="{Binding Map, Source={StaticResource MapViewModel}}"
                         GraphicsOverlays="{Binding GraphicsOverlays, Source={StaticResource MapViewModel}}"/>
   4 collapsed lines
   
       </Grid>
   
   </Window>

Add a UI for user input

The user will type an address into a text box and then click a button to execute a search. The MapViewModel class contains the logic to execute the search, but the controls are managed by the view.

1. In the Visual Studio > Solution Explorer, double-click MainWindow.xaml to open the file.

2. Add a Border above the map view that contains the address search controls.

   13 collapsed lines
   <Window x:Class="SearchForAnAddress.MainWindow"
           xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
           xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
           xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
           xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
           xmlns:local="clr-namespace:SearchForAnAddress"
           xmlns:esri="http://schemas.esri.com/arcgis/runtime/2013"
           mc:Ignorable="d"
           Title="MainWindow" Height="450" Width="800">
       <Window.Resources>
           <local:MapViewModel x:Key="MapViewModel" />
       </Window.Resources>
   
       <Grid>
   
           <esri:MapView x:Name="MainMapView"
                         Map="{Binding Map, Source={StaticResource MapViewModel}}"
                         GraphicsOverlays="{Binding GraphicsOverlays, Source={StaticResource MapViewModel}}"/>
   
           <Border Background="LightBlue"
                   HorizontalAlignment="Center" VerticalAlignment="Top"
                   Width="300" Height="60"
                   Margin="0,10">
               <Grid>
                   <Grid.RowDefinitions>
                       <RowDefinition Height="20"/>
                       <RowDefinition Height="30" />
                   </Grid.RowDefinitions>
                   <Grid.ColumnDefinitions>
                       <ColumnDefinition Width="3*" />
                       <ColumnDefinition Width="*" />
                   </Grid.ColumnDefinitions>
                   <TextBlock Text="Search for an address"
                              Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="2"
                              TextAlignment="Center" VerticalAlignment="Center"
                              FontWeight="SemiBold" />
                   <TextBox x:Name="AddressTextBox"
                            Grid.Row="1" Grid.Column="0"
                            Margin="5"
                            Text="380 New York Street, Redlands CA"/>
                   <Button x:Name="SearchAddressButton"
                           Grid.Row="1" Grid.Column="1"
                           Margin="5"
                           Content="Search"
                           Click="SearchAddressButton_Click" />
               </Grid>
           </Border>
   
       </Grid>
   2 collapsed lines
   
   </Window>

Create a function to geocode an address

Geocoding is implemented with a locator A locator is an ArcGIS dataset that stores address information and the rules for translating descriptions of places (such as street addresses or place names) into spatial data that can be displayed on a map. Learn more , typically created by referencing a geocoding service A geocoding service is a service that can search for addresses, place addresses, businesses, reverse geocode coordinates to addresses, provide suggestions for places, and perform bulk geocoding. It is hosted by Esri as the ArcGIS Geocoding service and can also be hosted in ArcGIS Enterprise. Learn more such as the Geocoding service or, for offline geocoding, by referencing locator data contained in a mobile package A mobile package is a stand-alone Mobile Map Package (MMPK) or Mobile Scene Package (MSPK) file for use in offline applications built with ArcGIS Maps SDKs for Native Apps. Learn more . Geocoding parameters can be used to fine-tune the results, such as setting the maximum number of results or requesting additional attributes in the results.

1. In the Visual Studio > Solution Explorer, double-click MapViewModel.cs to open the file.

2. Add a new function to search for an address and return its geographic location. The address string and a spatial reference (for output locations) are passed to the function. The function is marked async since it will make asynchronous calls using the await keyword.

   Returning values from async functions

   Asynchronous functions generally return Task<T>, where T is the type expected by the awaited call. In this function, when an address is geocoded, a MapPoint representing the address location is returned. If geocoding fails to find a match, null is returned.

   76 collapsed lines
   // Copyright 2021 Esri
   // Licensed under the Apache License, Version 2.0 (the "License");
   // you may not use this file except in compliance with the License.
   // You may obtain a copy of the License at
   //
   // https://www.apache.org/licenses/LICENSE-2.0
   //
   // Unless required by applicable law or agreed to in writing, software
   // distributed under the License is distributed on an "AS IS" BASIS,
   // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   // See the License for the specific language governing permissions and
   // limitations under the License.
   
   
   using System;
   using System.Collections.Generic;
   using Esri.ArcGISRuntime.Geometry;
   using Esri.ArcGISRuntime.Mapping;
   using System.ComponentModel;
   using System.Runtime.CompilerServices;
   
   using Esri.ArcGISRuntime.Symbology;
   using Esri.ArcGISRuntime.Tasks.Geocoding;
   using Esri.ArcGISRuntime.UI;
   using System.Drawing;
   using System.Linq;
   using System.Threading.Tasks;
   
   namespace SearchForAnAddress
   {
       class MapViewModel : INotifyPropertyChanged
       {
           public MapViewModel()
           {
               SetupMap();
           }
   
           public event PropertyChangedEventHandler? PropertyChanged;
           protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
           {
               var propertyChangedHandler = PropertyChanged;
               if (propertyChangedHandler != null)
                   propertyChangedHandler(this, new PropertyChangedEventArgs(propertyName));
           }
   
           private Map? _map;
           public Map? Map
           {
               get { return _map; }
               set
               {
                   _map = value;
                   OnPropertyChanged();
               }
           }
   
           private GraphicsOverlayCollection? _graphicsOverlayCollection;
           public GraphicsOverlayCollection? GraphicsOverlays
           {
               get { return _graphicsOverlayCollection; }
               set
               {
                   _graphicsOverlayCollection = value;
                   OnPropertyChanged();
               }
           }
   
           private void SetupMap()
           {
               // Create a new map with a 'topographic vector' basemap.
               Map map = new Map(BasemapStyle.ArcGISTopographic);
   
               // Set the initial viewpoint around the Santa Monica Mountains in California.
               var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);
               map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);
   
               // Set the view model "Map" property.
               this.Map = map;
   
               // Set the view model "GraphicsOverlays" property.
               GraphicsOverlay overlay = new GraphicsOverlay();
               GraphicsOverlayCollection overlayCollection = new GraphicsOverlayCollection
               {
                   overlay
               };
               this.GraphicsOverlays = overlayCollection;
   
           }
   
           public async Task<MapPoint?> SearchAddress(string address, SpatialReference spatialReference)
           {
               MapPoint? addressLocation = null;
   
               try
               {
   
               }
               catch (Exception ex)
               {
                   System.Windows.MessageBox.Show("Couldn't find address: " + ex.Message);
               }
   
               // Return the location of the geocode result.
               return addressLocation;
           }
   3 collapsed lines
   
       }
   }

3. Get the GraphicsOverlay and clear all of its Graphics.

   89 collapsed lines
   // Copyright 2021 Esri
   // Licensed under the Apache License, Version 2.0 (the "License");
   // you may not use this file except in compliance with the License.
   // You may obtain a copy of the License at
   //
   // https://www.apache.org/licenses/LICENSE-2.0
   //
   // Unless required by applicable law or agreed to in writing, software
   // distributed under the License is distributed on an "AS IS" BASIS,
   // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   // See the License for the specific language governing permissions and
   // limitations under the License.
   
   
   using System;
   using System.Collections.Generic;
   using Esri.ArcGISRuntime.Geometry;
   using Esri.ArcGISRuntime.Mapping;
   using System.ComponentModel;
   using System.Runtime.CompilerServices;
   
   using Esri.ArcGISRuntime.Symbology;
   using Esri.ArcGISRuntime.Tasks.Geocoding;
   using Esri.ArcGISRuntime.UI;
   using System.Drawing;
   using System.Linq;
   using System.Threading.Tasks;
   
   namespace SearchForAnAddress
   {
       class MapViewModel : INotifyPropertyChanged
       {
           public MapViewModel()
           {
               SetupMap();
           }
   
           public event PropertyChangedEventHandler? PropertyChanged;
           protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
           {
               var propertyChangedHandler = PropertyChanged;
               if (propertyChangedHandler != null)
                   propertyChangedHandler(this, new PropertyChangedEventArgs(propertyName));
           }
   
           private Map? _map;
           public Map? Map
           {
               get { return _map; }
               set
               {
                   _map = value;
                   OnPropertyChanged();
               }
           }
   
           private GraphicsOverlayCollection? _graphicsOverlayCollection;
           public GraphicsOverlayCollection? GraphicsOverlays
           {
               get { return _graphicsOverlayCollection; }
               set
               {
                   _graphicsOverlayCollection = value;
                   OnPropertyChanged();
               }
           }
   
           private void SetupMap()
           {
               // Create a new map with a 'topographic vector' basemap.
               Map map = new Map(BasemapStyle.ArcGISTopographic);
   
               // Set the initial viewpoint around the Santa Monica Mountains in California.
               var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);
               map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);
   
               // Set the view model "Map" property.
               this.Map = map;
   
               // Set the view model "GraphicsOverlays" property.
               GraphicsOverlay overlay = new GraphicsOverlay();
               GraphicsOverlayCollection overlayCollection = new GraphicsOverlayCollection
               {
                   overlay
               };
               this.GraphicsOverlays = overlayCollection;
   
           }
   
           public async Task<MapPoint?> SearchAddress(string address, SpatialReference spatialReference)
           {
               MapPoint? addressLocation = null;
   
               try
               {
   
                   // Get the first graphics overlay from the GraphicsOverlays and remove any previous result graphics.
                   GraphicsOverlay? graphicsOverlay = this.GraphicsOverlays?.FirstOrDefault();
                   graphicsOverlay?.Graphics.Clear();
   13 collapsed lines
   
               }
               catch (Exception ex)
               {
                   System.Windows.MessageBox.Show("Couldn't find address: " + ex.Message);
               }
   
               // Return the location of the geocode result.
               return addressLocation;
           }
   
       }
   }

4. Create a LocatorTask based on the Geocoding service.

   Finding locations or addresses

   A locator task is used to find the location of an address (geocode) or to interpolate an address for a location (reverse geocode). An address includes any type of information that distinguishes a place. A locator A locator is an ArcGIS dataset that stores address information and the rules for translating descriptions of places (such as street addresses or place names) into spatial data that can be displayed on a map. Learn more involves finding matching locations for a given address. Reverse-geocoding is the opposite and finds the closest address for a given location.

   96 collapsed lines
   // Copyright 2021 Esri
   // Licensed under the Apache License, Version 2.0 (the "License");
   // you may not use this file except in compliance with the License.
   // You may obtain a copy of the License at
   //
   // https://www.apache.org/licenses/LICENSE-2.0
   //
   // Unless required by applicable law or agreed to in writing, software
   // distributed under the License is distributed on an "AS IS" BASIS,
   // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   // See the License for the specific language governing permissions and
   // limitations under the License.
   
   
   using System;
   using System.Collections.Generic;
   using Esri.ArcGISRuntime.Geometry;
   using Esri.ArcGISRuntime.Mapping;
   using System.ComponentModel;
   using System.Runtime.CompilerServices;
   
   using Esri.ArcGISRuntime.Symbology;
   using Esri.ArcGISRuntime.Tasks.Geocoding;
   using Esri.ArcGISRuntime.UI;
   using System.Drawing;
   using System.Linq;
   using System.Threading.Tasks;
   
   namespace SearchForAnAddress
   {
       class MapViewModel : INotifyPropertyChanged
       {
           public MapViewModel()
           {
               SetupMap();
           }
   
           public event PropertyChangedEventHandler? PropertyChanged;
           protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
           {
               var propertyChangedHandler = PropertyChanged;
               if (propertyChangedHandler != null)
                   propertyChangedHandler(this, new PropertyChangedEventArgs(propertyName));
           }
   
           private Map? _map;
           public Map? Map
           {
               get { return _map; }
               set
               {
                   _map = value;
                   OnPropertyChanged();
               }
           }
   
           private GraphicsOverlayCollection? _graphicsOverlayCollection;
           public GraphicsOverlayCollection? GraphicsOverlays
           {
               get { return _graphicsOverlayCollection; }
               set
               {
                   _graphicsOverlayCollection = value;
                   OnPropertyChanged();
               }
           }
   
           private void SetupMap()
           {
               // Create a new map with a 'topographic vector' basemap.
               Map map = new Map(BasemapStyle.ArcGISTopographic);
   
               // Set the initial viewpoint around the Santa Monica Mountains in California.
               var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);
               map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);
   
               // Set the view model "Map" property.
               this.Map = map;
   
               // Set the view model "GraphicsOverlays" property.
               GraphicsOverlay overlay = new GraphicsOverlay();
               GraphicsOverlayCollection overlayCollection = new GraphicsOverlayCollection
               {
                   overlay
               };
               this.GraphicsOverlays = overlayCollection;
   
           }
   
           public async Task<MapPoint?> SearchAddress(string address, SpatialReference spatialReference)
           {
               MapPoint? addressLocation = null;
   
               try
               {
   
                   // Get the first graphics overlay from the GraphicsOverlays and remove any previous result graphics.
                   GraphicsOverlay? graphicsOverlay = this.GraphicsOverlays?.FirstOrDefault();
                   graphicsOverlay?.Graphics.Clear();
   
                   // Create a locator task.
                   LocatorTask locatorTask = new LocatorTask(new Uri("https://geocode-api.arcgis.com/arcgis/rest/services/World/GeocodeServer"));
   13 collapsed lines
   
               }
               catch (Exception ex)
               {
                   System.Windows.MessageBox.Show("Couldn't find address: " + ex.Message);
               }
   
               // Return the location of the geocode result.
               return addressLocation;
           }
   
       }
   }

5. Create a new GeocodeParameters and define some of its properties.

   • Add the names of attributes to return to the GeocodeParameters.ResultAttributeNames collection. An asterisk (*) indicates all attributes.
   • Set the maximum number of results to be returned with GeocodeParameters.MaxResults. Results are ordered by score, so that the first result has the best match score (ranging from 0 for no match to 100 for the best match).
   • Set the spatial reference A spatial reference is a set of parameters, typically defined by a WKID, that define the coordinate system and spatial properties for geographic data. Applications use a spatial reference to correctly display the position of geographic data in a map or scene. Learn more for result locations with GeocodeParameters.OutputSpatialReference. By default, the output spatial reference is defined by the geocode service. For optimal performance when displaying the geocode result, you can ensure that returned coordinates match those of the map view by providing the map view’s spatial reference.
   Geocoding parameters

   When geocoding an address, you can optionally provide GeocodeParameters to control certain aspects of the geocoding operation and specify the kinds of results to return from the locator task. Learn more about these parameters in the GeocodeParameters. For a list of attributes returned with geocode results, see Geocoding service output in the ArcGIS services reference.

   100 collapsed lines
   // Copyright 2021 Esri
   // Licensed under the Apache License, Version 2.0 (the "License");
   // you may not use this file except in compliance with the License.
   // You may obtain a copy of the License at
   //
   // https://www.apache.org/licenses/LICENSE-2.0
   //
   // Unless required by applicable law or agreed to in writing, software
   // distributed under the License is distributed on an "AS IS" BASIS,
   // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   // See the License for the specific language governing permissions and
   // limitations under the License.
   
   
   using System;
   using System.Collections.Generic;
   using Esri.ArcGISRuntime.Geometry;
   using Esri.ArcGISRuntime.Mapping;
   using System.ComponentModel;
   using System.Runtime.CompilerServices;
   
   using Esri.ArcGISRuntime.Symbology;
   using Esri.ArcGISRuntime.Tasks.Geocoding;
   using Esri.ArcGISRuntime.UI;
   using System.Drawing;
   using System.Linq;
   using System.Threading.Tasks;
   
   namespace SearchForAnAddress
   {
       class MapViewModel : INotifyPropertyChanged
       {
           public MapViewModel()
           {
               SetupMap();
           }
   
           public event PropertyChangedEventHandler? PropertyChanged;
           protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
           {
               var propertyChangedHandler = PropertyChanged;
               if (propertyChangedHandler != null)
                   propertyChangedHandler(this, new PropertyChangedEventArgs(propertyName));
           }
   
           private Map? _map;
           public Map? Map
           {
               get { return _map; }
               set
               {
                   _map = value;
                   OnPropertyChanged();
               }
           }
   
           private GraphicsOverlayCollection? _graphicsOverlayCollection;
           public GraphicsOverlayCollection? GraphicsOverlays
           {
               get { return _graphicsOverlayCollection; }
               set
               {
                   _graphicsOverlayCollection = value;
                   OnPropertyChanged();
               }
           }
   
           private void SetupMap()
           {
               // Create a new map with a 'topographic vector' basemap.
               Map map = new Map(BasemapStyle.ArcGISTopographic);
   
               // Set the initial viewpoint around the Santa Monica Mountains in California.
               var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);
               map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);
   
               // Set the view model "Map" property.
               this.Map = map;
   
               // Set the view model "GraphicsOverlays" property.
               GraphicsOverlay overlay = new GraphicsOverlay();
               GraphicsOverlayCollection overlayCollection = new GraphicsOverlayCollection
               {
                   overlay
               };
               this.GraphicsOverlays = overlayCollection;
   
           }
   
           public async Task<MapPoint?> SearchAddress(string address, SpatialReference spatialReference)
           {
               MapPoint? addressLocation = null;
   
               try
               {
   
                   // Get the first graphics overlay from the GraphicsOverlays and remove any previous result graphics.
                   GraphicsOverlay? graphicsOverlay = this.GraphicsOverlays?.FirstOrDefault();
                   graphicsOverlay?.Graphics.Clear();
   
                   // Create a locator task.
                   LocatorTask locatorTask = new LocatorTask(new Uri("https://geocode-api.arcgis.com/arcgis/rest/services/World/GeocodeServer"));
   
                   // Define geocode parameters: limit the results to one and get all attributes.
                   GeocodeParameters geocodeParameters = new GeocodeParameters();
                   geocodeParameters.ResultAttributeNames.Add("*");
                   geocodeParameters.MaxResults = 1;
                   geocodeParameters.OutputSpatialReference = spatialReference;
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               }
               catch (Exception ex)
               {
                   System.Windows.MessageBox.Show("Couldn't find address: " + ex.Message);
               }
   
               // Return the location of the geocode result.
               return addressLocation;
           }
   
       }
   }

6. To find the location for the provided address, call LocatorTask.GeocodeAsync, providing the address string and geocodeParameters. The result is a read-only list of GeocodeResult objects. In this tutorial, either one or zero results will be returned, as the maximum results parameter was set to 1.

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   // Copyright 2021 Esri
   // Licensed under the Apache License, Version 2.0 (the "License");
   // you may not use this file except in compliance with the License.
   // You may obtain a copy of the License at
   //
   // https://www.apache.org/licenses/LICENSE-2.0
   //
   // Unless required by applicable law or agreed to in writing, software
   // distributed under the License is distributed on an "AS IS" BASIS,
   // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   // See the License for the specific language governing permissions and
   // limitations under the License.
   
   
   using System;
   using System.Collections.Generic;
   using Esri.ArcGISRuntime.Geometry;
   using Esri.ArcGISRuntime.Mapping;
   using System.ComponentModel;
   using System.Runtime.CompilerServices;
   
   using Esri.ArcGISRuntime.Symbology;
   using Esri.ArcGISRuntime.Tasks.Geocoding;
   using Esri.ArcGISRuntime.UI;
   using System.Drawing;
   using System.Linq;
   using System.Threading.Tasks;
   
   namespace SearchForAnAddress
   {
       class MapViewModel : INotifyPropertyChanged
       {
           public MapViewModel()
           {
               SetupMap();
           }
   
           public event PropertyChangedEventHandler? PropertyChanged;
           protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
           {
               var propertyChangedHandler = PropertyChanged;
               if (propertyChangedHandler != null)
                   propertyChangedHandler(this, new PropertyChangedEventArgs(propertyName));
           }
   
           private Map? _map;
           public Map? Map
           {
               get { return _map; }
               set
               {
                   _map = value;
                   OnPropertyChanged();
               }
           }
   
           private GraphicsOverlayCollection? _graphicsOverlayCollection;
           public GraphicsOverlayCollection? GraphicsOverlays
           {
               get { return _graphicsOverlayCollection; }
               set
               {
                   _graphicsOverlayCollection = value;
                   OnPropertyChanged();
               }
           }
   
           private void SetupMap()
           {
               // Create a new map with a 'topographic vector' basemap.
               Map map = new Map(BasemapStyle.ArcGISTopographic);
   
               // Set the initial viewpoint around the Santa Monica Mountains in California.
               var mapCenterPoint = new MapPoint(-118.805, 34.027, SpatialReferences.Wgs84);
               map.InitialViewpoint = new Viewpoint(mapCenterPoint, 100000);
   
               // Set the view model "Map" property.
               this.Map = map;
   
               // Set the view model "GraphicsOverlays" property.
               GraphicsOverlay overlay = new GraphicsOverlay();
               GraphicsOverlayCollection overlayCollection = new GraphicsOverlayCollection
               {
                   overlay
               };
               this.GraphicsOverlays = overlayCollection;
   
           }
   
           public async Task<MapPoint?> SearchAddress(string address, SpatialReference spatialReference)
           {
               MapPoint? addressLocation = null;
   
               try
               {
   
                   // Get the first graphics overlay from the GraphicsOverlays and remove any previous result graphics.
                   GraphicsOverlay? graphicsOverlay = this.GraphicsOverlays?.FirstOrDefault();
                   graphicsOverlay?.Graphics.Clear();
   
                   // Create a locator task.
                   LocatorTask locatorTask = new LocatorTask(new Uri("https://geocode-api.arcgis.com/arcgis/rest/services/World/GeocodeServer"));
   
                   // Define geocode parameters: limit the results to one and get all attributes.
                   GeocodeParameters geocodeParameters = new GeocodeParameters();
                   geocodeParameters.ResultAttributeNames.Add("*");
                   geocodeParameters.MaxResults = 1;
                   geocodeParameters.OutputSpatialReference = spatialReference;
   
                   // Geocode the address string and get the first (only) result.
                   IReadOnlyList<GeocodeResult> results = await locatorTask.GeocodeAsync(address, geocodeParameters);
                   GeocodeResult? geocodeResult = results[0];
                   if(geocodeResult == null) { throw new Exception("No matches found."); }
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               }
               catch (Exception ex)
               {
                   System.Windows.MessageBox.Show("Couldn't find address: " + ex.Message);
               }
   
               // Return the location of the geocode result.
               return addressLocation;
           }
   
       }
   }