Query

This sample demonstrates using an ESRI.ArcGIS.Client.Tasks QueryTask class to Query an ArcGISImageServiceLayer to find and display the outlines of image tiles and display them as SimpleFillSymbols in a GraphicsLayer. MapTips containing attribute information is displayed for those tiles that are returned from the Query when the mouse is hovered over them. To use this sample, drag a rectangle to query image tiles. Tile footprints will be displayed and their attributes will be available in map tips.

XAML

<UserControl x:Class="ArcGISWPFSDK.QueryImageService"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:esri="http://schemas.esri.com/arcgis/client/2009"
    xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity">
    <Grid x:Name="LayoutRoot" Background="White">

        <Grid.Resources>
            <esri:SimpleFillSymbol x:Key="DrawFillSymbol" BorderBrush="Red" Fill="#33FF0000" />
            <esri:SimpleFillSymbol x:Key="FootprintFillSymbol" Fill="#01FFFFFF" BorderBrush="White" BorderThickness="2" />
            <LinearGradientBrush x:Key="PanelGradient" EndPoint="0.5,1" StartPoint="0.5,0">
                <LinearGradientBrush.RelativeTransform>
                    <TransformGroup>
                        <ScaleTransform CenterY="0.5" CenterX="0.5"/>
                        <SkewTransform CenterY="0.5" CenterX="0.5"/>
                        <RotateTransform Angle="176" CenterY="0.5" CenterX="0.5"/>
                        <TranslateTransform/>
                    </TransformGroup>
                </LinearGradientBrush.RelativeTransform>
                <GradientStop Color="#FF145787" Offset="0.16"/>
                <GradientStop Color="#FF3D7FAC" Offset="0.502"/>
                <GradientStop Color="#FF88C5EF" Offset="0.984"/>
            </LinearGradientBrush>
        </Grid.Resources>

        <esri:Map x:Name="MyMap" MinimumResolution="0.001" WrapAround="True">
            <esri:Map.Extent>
                <esri:Envelope XMin="-13670997.592674" YMin="5697204.89662362" XMax="-13637149.3323152" YMax="5714270.45407472">
                    <esri:Envelope.SpatialReference>
                        <esri:SpatialReference WKID="102100"/>
                    </esri:Envelope.SpatialReference>
                </esri:Envelope>
            </esri:Map.Extent>
            <esri:ArcGISImageServiceLayer ID="ImageServiceLayer"  
                    Url="http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/Portland/Aerial/ImageServer" ImageFormat="JPGPNG" />
            <esri:ArcGISTiledMapServiceLayer Opacity="100" 
                    Url="http://services.arcgisonline.com/ArcGIS/rest/services/Reference/World_Transportation/MapServer" />
            <esri:GraphicsLayer ID="FootprintsGraphicsLayer" >
                <esri:GraphicsLayer.MapTip>
                    <Border CornerRadius="10" BorderBrush="#FF222957" Background="LightGray" BorderThickness="2" Margin="0,0,15,15">
                        <StackPanel Orientation="Vertical" Margin="5">
                            <StackPanel Orientation="Horizontal">
                                <TextBlock Text="Name: " FontWeight="Bold"  Foreground="Black" />
                                <TextBlock Text="{Binding [Name]}"  Foreground="Black" />
                            </StackPanel>
                            <StackPanel Orientation="Horizontal">
                                <TextBlock Text="Pixel Size (meters/pixel): "  Foreground="Black" />
                                <TextBlock Text="{Binding [LowPS]}"  Foreground="Black" />
                            </StackPanel>
                        </StackPanel>
                    </Border>
                </esri:GraphicsLayer.MapTip>
            </esri:GraphicsLayer>
        </esri:Map>

        <Grid HorizontalAlignment="Right" VerticalAlignment="Top" Margin="0,10,10,0" >
            <Rectangle Fill="{StaticResource PanelGradient}" Stroke="Gray"  RadiusX="10" RadiusY="10" Margin="0,0,0,5">
                <Rectangle.Effect>
                    <DropShadowEffect/>
                </Rectangle.Effect>
            </Rectangle>
            <Rectangle Fill="#FFFFFFFF" Stroke="DarkGray" RadiusX="5" RadiusY="5" Margin="10,10,10,15" />
            <StackPanel Orientation="Vertical" Margin="30,20,20,30" >
                <TextBlock x:Name="ResponseTextBlock" Text="Drag a rectangle to query image tiles.  Tile footprints will be displayed and their attributes will be available in map tips." 
                           Width="200" TextAlignment="Left"  TextWrapping="Wrap"  Foreground="Black" />
                <Button Content="Clear Results" Margin="0,5,5,0" Click="ClearButton_Click"  />
            </StackPanel>
        </Grid>

    </Grid>
</UserControl>

C#

using System;
using System.Windows;
using System.Windows.Controls;
using ESRI.ArcGIS.Client;
using ESRI.ArcGIS.Client.Tasks;

namespace ArcGISWPFSDK
{
    public partial class QueryImageService : UserControl
    {
        private Draw myDrawObject;
        private GraphicsLayer footprintsGraphicsLayer;

        public QueryImageService()
        {
            InitializeComponent();

            myDrawObject = new Draw(MyMap)
            {
                DrawMode = DrawMode.Rectangle,
                FillSymbol = LayoutRoot.Resources["DrawFillSymbol"] as ESRI.ArcGIS.Client.Symbols.FillSymbol,
                IsEnabled = true
            };

            myDrawObject.DrawComplete += MyDrawObject_DrawComplete;
            footprintsGraphicsLayer = MyMap.Layers["FootprintsGraphicsLayer"] as GraphicsLayer;
        }

        private void MyDrawObject_DrawComplete(object sender, ESRI.ArcGIS.Client.DrawEventArgs args)
        {
            myDrawObject.IsEnabled = false;

            QueryTask queryTask = new QueryTask("http://servicesbeta.esri.com/ArcGIS/rest/services/Portland/PortlandAerial/ImageServer/query");
            queryTask.ExecuteCompleted += QueryTask_ExecuteCompleted;
            queryTask.Failed += QueryTask_Failed;

            Query query = new ESRI.ArcGIS.Client.Tasks.Query();
            query.OutFields.Add("*");
            query.Geometry = args.Geometry;
            query.ReturnGeometry = true;
            query.OutSpatialReference = MyMap.SpatialReference;
            query.Where = "Category = 1";

            queryTask.ExecuteAsync(query);
        }

        private void QueryTask_ExecuteCompleted(object sender, ESRI.ArcGIS.Client.Tasks.QueryEventArgs args)
        {
            FeatureSet featureSet = args.FeatureSet;

            if (featureSet == null || featureSet.Features.Count < 1)
            {
                MessageBox.Show("No features retured from query");
                return;
            }

            if (featureSet != null && featureSet.Features.Count > 0)
            {
                foreach (Graphic graphic in featureSet.Features)
                {
                    graphic.Symbol = LayoutRoot.Resources["FootprintFillSymbol"] as ESRI.ArcGIS.Client.Symbols.FillSymbol;
                    footprintsGraphicsLayer.Graphics.Add(graphic);
                }
            }

            myDrawObject.IsEnabled = true;
        }

        private void QueryTask_Failed(object sender, TaskFailedEventArgs args)
        {
            MessageBox.Show("Query failed: " + args.Error);
        }

        private void ClearButton_Click(object sender, RoutedEventArgs e)
        {
            footprintsGraphicsLayer.ClearGraphics();
        }

    }
}

VB.NET

Imports System.Windows
Imports System.Windows.Controls
Imports ESRI.ArcGIS.Client
Imports ESRI.ArcGIS.Client.Tasks

Namespace ArcGISWPFSDK
    Partial Public Class QueryImageService
        Inherits UserControl
        Private myDrawObject As Draw
        Private footprintsGraphicsLayer As GraphicsLayer

        Public Sub New()
            InitializeComponent()

            myDrawObject = New Draw(MyMap) With { _
             .DrawMode = DrawMode.Rectangle, _
             .FillSymbol = TryCast(LayoutRoot.Resources("DrawFillSymbol"), ESRI.ArcGIS.Client.Symbols.FillSymbol), _
             .IsEnabled = True _
            }

            AddHandler myDrawObject.DrawComplete, AddressOf MyDrawObject_DrawComplete
            footprintsGraphicsLayer = TryCast(MyMap.Layers("FootprintsGraphicsLayer"), GraphicsLayer)
        End Sub

        Private Sub MyDrawObject_DrawComplete(sender As Object, args As ESRI.ArcGIS.Client.DrawEventArgs)
            myDrawObject.IsEnabled = False

            Dim queryTask As New QueryTask("http://servicesbeta.esri.com/ArcGIS/rest/services/Portland/PortlandAerial/ImageServer/query")
            AddHandler queryTask.ExecuteCompleted, AddressOf QueryTask_ExecuteCompleted
            AddHandler queryTask.Failed, AddressOf QueryTask_Failed

            Dim query As Query = New ESRI.ArcGIS.Client.Tasks.Query()
            query.OutFields.Add("*")
            query.Geometry = args.Geometry
            query.ReturnGeometry = True
            query.OutSpatialReference = MyMap.SpatialReference
            query.Where = "Category = 1"

            queryTask.ExecuteAsync(query)
        End Sub

        Private Sub QueryTask_ExecuteCompleted(sender As Object, args As ESRI.ArcGIS.Client.Tasks.QueryEventArgs)
            Dim featureSet As FeatureSet = args.FeatureSet

            If featureSet Is Nothing OrElse featureSet.Features.Count < 1 Then
                MessageBox.Show("No features retured from query")
                Return
            End If

            If featureSet IsNot Nothing AndAlso featureSet.Features.Count > 0 Then
                For Each graphic As Graphic In featureSet.Features
                    graphic.Symbol = TryCast(LayoutRoot.Resources("FootprintFillSymbol"), ESRI.ArcGIS.Client.Symbols.FillSymbol)
                    footprintsGraphicsLayer.Graphics.Add(graphic)
                Next
            End If

            myDrawObject.IsEnabled = True
        End Sub

        Private Sub QueryTask_Failed(sender As Object, args As TaskFailedEventArgs)
            MessageBox.Show("Query failed: " & Convert.ToString(args.[Error]))
        End Sub

        Private Sub ClearButton_Click(sender As Object, e As RoutedEventArgs)
            footprintsGraphicsLayer.ClearGraphics()
        End Sub

    End Class
End Namespace