topic Re: How to perform spatial query between two services... in ArcGIS API for Silverlight Questions

How to perform spatial query between two services...

MichaelBlom — Thu, 15 Jul 2010 11:45:56 GMT

Hello,
all of the sdk examples involving spatial qeuries involve a service being queried against a feature that the user creates in th UI.

ie drag a box, take the geometry from that box, set that geometry into the query, perform task

I want to do a query task between two service layers.

I see that I need to get at the recordset from the service in Silverlight, does anyone know how to do this?

Thanks,
Mike

Re: How to perform spatial query between two services...

MichaelBlom — Thu, 15 Jul 2010 13:24:08 GMT

answering my own question:

within the xaml for my ArcGISDynamicMapServiceLayer, i provide a call to a method for Initialized

in the code behind: var dynamicService = sender as ArcGISDynamicMapServiceLayer;

get the layerinfos: foreach (LayerInfo fl in dynamicService.Layers)

Re: How to perform spatial query between two services...

JMcNeil — Thu, 16 Sep 2010 19:42:21 GMT

Mike,
I am looking to do something similar. I'm wondering if I could see your code or ask you a few questions.

Thanks
Jay
jmcneil@escondido.org

Re: How to perform spatial query between two services...

SourishChakraborty — Fri, 17 Sep 2010 08:13:53 GMT

Hi,
Please clarify a little;
There may be a scenario where multiple layers are there in a service.You can query one layer with the features of other layer from the same service.

There may be a scenario where two layers are from different services.You can query one service layer by using the features of other service layer.

Which scenario you want to use.

Thanks & Regards
Sourish Chakraborty

Re: How to perform spatial query between two services...

JMcNeil — Mon, 20 Sep 2010 14:24:59 GMT

After reading Mike's and your post I'm thinking he was trying something different. Basically, I have implemented the Spatial Query tools.....straight forward and super easy; grabbed the xaml and code behind C# from the interactive sdk ( http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#SpatialQuery ) but I would really like to give the user the option to do spatial queries on multiple/several layers (not multiple layers at the same time but the user selects an active layer to perform the query on probably from one service but being able to select layers from two or three services might be an option because there will be several services that make up the map).

I built a layer list for my application that allows the user to check check boxes to turn on/off layers so I was thinking I could create radio buttons for each layer, which would drive the active layer or I could create a drop down list of all the layers in the map and this could drive the active layer.

What I'm kind of lost and twisted about is how to change my fields and data table headers based on the active layer. The spatial query interactive SDK sample ( http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#SpatialQuery ) hard codes all the fields and table field names. Maybe somehow there is a way to query the active service/layer and dynamically populate some Collection object, or maybe have an XML file that is hard coded and that populates the table. What about global variables of the layer name, fields, headers, etc. Then when the user submits the query, set the query parameters from the global variables. Or just bind them to those variables.

Not sure setting the active layer seems straight forward and I think I can handle that I am just having a hard time thinking of how to populate the table and I guess I'm was hoping to sneak a peak at something to jump start my process.

Re: How to perform spatial query between two services...

ChristineZeller — Fri, 08 Oct 2010 02:33:24 GMT

answering my own question:

within the xaml for my ArcGISDynamicMapServiceLayer, i provide a call to a method for Initialized

in the code behind: var dynamicService = sender as ArcGISDynamicMapServiceLayer;

get the layerinfos: foreach (LayerInfo fl in dynamicService.Layers)

Mike like Mr. Lennon

I am looking to do something similar and was also wondering if you wouldn't mind sharing your call to method for initialized and your foreach (LayerInfo fl in dynamicService.Layers) loop with a little more detail. I'm somewhat fresh/green and have an idea on how it should be done but having trouble.

Christine.

Re: How to perform spatial query between two services...

JMcNeil — Sat, 11 Dec 2021 19:59:51 GMT

Christine, Mike, blomm or anyone else interested in this post!

I finally found a little time to try and get the SDK spatial tool to work with muiltiple layers, using a combo drop down box. I'm almost there and now I'm having a freeze about how to handle the xaml end........populating the headers and fields for the datagrid. This Part:

 <!-- Query Results -->

                                            <slData:DataGrid x:Name="QueryDetailsDataGrid" AutoGenerateColumns="False" HeadersVisibility="Column" Background="White" 
                                IsReadOnly="True" HorizontalScrollBarVisibility="Hidden"
                             RowStyle="{StaticResource MyCustomRow}" CanUserSortColumns="True"
                             SelectionChanged="QueryDetailsDataGrid_SelectionChanged"
                             LoadingRow="QueryDetailsDataGrid_LoadingRow">                                               
                                                         <slData:DataGrid.Columns>
                                                            <slData:DataGridTextColumn Binding="{Binding Attributes[BVUNIQUEID]}" Header="BV UNIQUE ID"/>
                                                            <slData:DataGridTextColumn Binding="{Binding Attributes[CREZ_NAME]}" Header="CREZ NAME"/>
                                                            <slData:DataGridTextColumn Binding="{Binding Attributes[SOLARTH_MW]}" Header="SOLARTH MW"/>
                                                            <slData:DataGridTextColumn Binding="{Binding Attributes[ACRES]}" Header="ACRES"/>
                                                        </slData:DataGrid.Columns>
                                                    </slData:DataGrid>
                                            
                                            
                                            
                                                </ScrollViewer>
                                          
                                    </Grid>
                                </userControls:CollapsiblePanel>
                                
                       
                                <!-- End Query Results -->

So Like I said I add a drop down list in xaml, which is used to select which layer is active.

 <!--Jays DropDown List / Combo Box for Spatial Selection -->


                            <ComboBox x:Name="LayerListDropDown" Width="150" Height="30" VerticalAlignment="Bottom" HorizontalAlignment="Center"  Margin="0,5,0,5" SelectionChanged="DropDown_ItemSelected">
                                
                                <ComboBoxItem Content="layer1" />
                                <ComboBoxItem Content="layer2" />
                                <ComboBoxItem Content="layer3" />
                               
                            </ComboBox>


                            <!--Jays DropDown List / Combo Box for Spatial Selection -->

In my code behind I add this

 #region LayerListDropDown Code
        //layerlist dropdown code


        private void DropDown_ItemSelected(object sender, EventArgs e)
        {

            if (LayerListDropDown.SelectedIndex == 0)
            {
       
                UrlServiceId = "http://dgpdch01/ArcGIS/rest/services/testD2/MapServer/14";
            }

            else if (LayerListDropDown.SelectedIndex == 1)
            {
      
                UrlServiceId = "http://dgpdch01/ArcGIS/rest/services/testD2/MapServer/18";
            }

            else
            {
        
                UrlServiceId = "http://dgpdch01/ArcGIS/rest/services/testD2/MapServer/19";
            }


            _queryTask = new QueryTask(UrlServiceId);
            _queryTask.ExecuteCompleted += QueryTask_ExecuteCompleted;
            _queryTask.Failed += QueryTask_Failed;

        }

        #endregion

and in the method

private void MyDrawSurface_DrawComplete(object sender, ESRI.ArcGIS.Client.DrawEventArgs args)

I add this

 //Jay add for if else drop list.

             if (LayerListDropDown.SelectedIndex == 0)
            {
                query.OutFields.AddRange(new string[] { "BVUNIQUEID", "ACRES", "CREZ_NAME", "SOLARTH_MW" }); 
            }

            else if (LayerListDropDown.SelectedIndex == 1)
            {
                query.OutFields.AddRange(new string[] { "PROJECTTYP", "CREZ_BVID", "CREZ_NAME", "MW", "CALCULATED"}); 
            }

            else
            {
                query.OutFields.AddRange(new string[] { "PROJECT_ID", "ASSOC_CREZ", "ACRES", "CREZ_BVID", "GISCALC" }); 
            }

So now the user can select a layer and spatial query on the selected layer but the field name it is trying to pull and field headers are static. Also right now it is only working with polygon layers. Once I get polys down I will write story/animation so lines and markers work but

What should I do to switch what is being Generater in the QueryDetailsDataGrid GRID (the first xaml code I posted or to be really specific I only need to change the column data....see below).

Should I handle this with hiding and showing animation/grids or is there a way to do like a if/else in xaml or add some event trigge and checked if that is checked (EventTrigger EventName="Checked") but the check should be the drop down list so it would be really easy to just do an if/else

Late in the day and I can't think......plus I'm a hack.

<slData:DataGrid.Columns>
                                                            <slData:DataGridTextColumn Binding="{Binding Attributes[BVUNIQUEID]}" Header="BV UNIQUE ID"/>
                                                            <slData:DataGridTextColumn Binding="{Binding Attributes[CREZ_NAME]}" Header="CREZ NAME"/>
                                                            <slData:DataGridTextColumn Binding="{Binding Attributes[SOLARTH_MW]}" Header="SOLARTH MW"/>
                                                            <slData:DataGridTextColumn Binding="{Binding Attributes[ACRES]}" Header="ACRES"/>
                                                 </slData:DataGrid.Columns>

Re: How to perform spatial query between two services...

JMcNeil — Sat, 11 Dec 2021 19:59:53 GMT

O.K.
I got a little more time today and made no progress I was thinking something like a datatrigger but I don't even know if that is possible in Silverlight....I couldn't find the ref to add or it wouldn't let me add it. I gave Interaction.Triggers and EventTrigger a thought but on what?

So I just thought keep it simple and basic....like most of my coding. So I add a few variables in my CODE behind - MainPage.xaml.cs and declared them up where the other variable are declared and assigned them in the if/else statement (see code below for that ref.)



        private void MyDrawSurface_DrawComplete(object sender, ESRI.ArcGIS.Client.DrawEventArgs args)
        {
            GraphicsLayer selectionGraphicslayer = Map.Layers["MySelectionGraphicsLayer"] as GraphicsLayer;
            selectionGraphicslayer.ClearGraphics();

            // Bind data grid to query results
            Binding resultFeaturesBinding = new Binding("LastResult.Features");
            resultFeaturesBinding.Source = _queryTask;
            QueryDetailsDataGrid.SetBinding(DataGrid.ItemsSourceProperty, resultFeaturesBinding);

            Query query = new ESRI.ArcGIS.Client.Tasks.Query();


            

            //Jay add for if else drop list.

             if (LayerListDropDown.SelectedIndex == 0)
            {




                Field1 = "BVUNIQUEID";
                Field2 = "ACRES";
                Field3 = "CREZ_NAME";
                Field4 = "SOLARTH_MW";

                query.OutFields.AddRange(new string[] { Field1, Field2, Field3, Field4 });


               

            

            }

            else if (LayerListDropDown.SelectedIndex == 1)
            {

And this works but when flip back to my xaml where the attributes are binded.

I can't pass my varialbe and bind that


<slData:DataGrid.Columns>

<!-- This dies -->
<slData:DataGridTextColumn Binding= "{Binding Attributes[Field1]}" Header= Field1/>

<!-- These still work -->
 <slData:DataGridTextColumn Binding="{Binding Attributes[ACRES]}" Header="CREZ NAME"/>
 <slData:DataGridTextColumn Binding="{Binding Attributes[SOLARTH_MW]}" Header="SOLARTH MW"/>
     <slData:DataGridTextColumn Binding="{Binding Attributes[ACRES]}" Header="ACRES"/>
 </slData:DataGrid.Columns>

Which makes sense....

SO I'm Pleading for help and apologizing that this post is growing and growing and growing with no resolution.... sort of like the Bing Map does not show up post and the Area And Perimeter, which I haven't looked at yet but I promise I will try to help solve them if someone helps me! And that will clear 3 posts that are constantly on the top of this board.

Re: How to perform spatial query between two services...

JenniferNery — Sat, 11 Dec 2021 19:59:57 GMT

Can you just use FeatureDataGrid instead? Bind Map to your map and GraphicsLayer to your SelectionGraphicsLayer, since the query results are added to your GraphicsLayer.


                <esri:FeatureDataGrid Grid.Row="1" x:Name="QueryDetailsDataGrid" Height="170" 
                                      Map="{Binding ElementName=MyMap}" 
                                      GraphicsLayer="{Binding ElementName=MyMap, Path=Layers[MySelectionGraphicsLayer]}" />

Your ComboBox can probably contain FeatureLayers:
XAML-code

                <ComboBox x:Name="Layers" >
                    <ComboBox.ItemTemplate>
                        <DataTemplate>
                            <TextBlock Text="{Binding LayerInfo.Name}"/>
                        </DataTemplate>
                    </ComboBox.ItemTemplate>
                </ComboBox>

Code-behind (maybe after Initialize)

            string baseUrl = "http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Demographics/ESRI_Census_USA/MapServer";
            for (int i = 0; i <= 5; i++)
            {
                FeatureLayer featureLayer = new FeatureLayer() { Url = string.Format("{0}/{1}", baseUrl, i)};
                featureLayer.Initialize();
                layers.Add(featureLayer);
            }
            Layers.ItemsSource = layers;
            Layers.SelectedIndex = 0;

Also, I would tweak the query to return all fields.

            QueryTask queryTask = new QueryTask((Layers.SelectedItem as FeatureLayer).Url);
            //... more code here
            query.OutFields.Add("*");

Re: How to perform spatial query between two services...

JMcNeil — Wed, 20 Oct 2010 16:01:55 GMT

Jennifer, thanks for the reply! I didn't think of using FeatureDataGrid instead.

Just glancing at your code you posted. What do I declare the layers and query variables as. I don�??t think they exist in my current code.

I think the layers maybe should be:

ItemCollection layers;

But what about the query is that a property of the Outfields constructor, like an Item? Or is it a list? How should I declare it? Sorry for the confusion.

Re: How to perform spatial query between two services...

JenniferNery — Wed, 20 Oct 2010 16:08:39 GMT

Oh I'm sorry I missed to include that - layers in my sample is of type ObservableCollection<FeatureLayer>.

Re: How to perform spatial query between two services...

JMcNeil — Wed, 20 Oct 2010 16:56:02 GMT

Oh I'm sorry I missed to include that - layers in my sample is of type ObservableCollection<FeatureLayer>.

Jennifer, thanks for the quick response.

I feel horrible that I can't get this....I'm just lost!

Like - Inherited from System.Collections.ObjectModel.ObservableCollection<Graphic>
And you said that is for layer?

What about query?

J.

Re: How to perform spatial query between two services...

JenniferNery — Sat, 11 Dec 2021 19:59:59 GMT

If your ComboBox is named "Layers" with ItemSource bound to ObservableCollection<FeatureLayer> as described in my previous post, you can modify your query this way:

 
            QueryTask queryTask = new QueryTask((Layers.SelectedItem as FeatureLayer).Url);
            //... more code here
            query.OutFields.Add("*");

That is Layers.SelectedItem is FeatureLayer and is not null, you can grab it's Url.

This was just one way to do it, you can have instead an list of url strings in your ComboBox and perform your query against the selected string.

Since you don't know what fields that layer will contain and don't want to hard-code it, you can just return all fields by using "*", no need to specify AddRange(new string[]{ "field1", "field2", ...}).

I suggested using FeatureLayer incase you wish to see the LayerInfo.Fields before performing the query. You can get these values after the layer has been initialized.

Re: How to perform spatial query between two services...

JMcNeil — Sat, 11 Dec 2021 20:00:03 GMT

Jennifer. Thanks again for all the replies. I started over straight with the Spatial Query SDK because my code was twisted and I had a bunch of extra stuff that was getting more confused.

I add the two xaml code snippits exactly how you wrote them.

The I tried to implement your code behind but app hangs and I do get the error warning about
ObservableCollection<FeatureLayer> layers; - is never assigned and always has a defualt value of null.....I'm sorry but what I'm I missing.

 public partial class MainPage : UserControl
    {

  private Draw MyDrawSurface;

  ObservableCollection<FeatureLayer> layers;

        public MainPage()
        {
            InitializeComponent();

           

            string baseUrl = "http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Demographics/ESRI_Census_USA/MapServer";

            for (int i = 0; i <= 5; i++)
            {
                FeatureLayer featureLayer = new FeatureLayer() { Url = string.Format("{0}/{1}", baseUrl, i) };
                featureLayer.Initialize();
                layers.Add(featureLayer);
            }
            Layers.ItemsSource = layers;
            Layers.SelectedIndex = 0;

           
            MyDrawSurface = new Draw(MyMap)
            {
              LineSymbol = LayoutRoot.Resources["DefaultLineSymbol"] as SimpleLineSymbol,
              FillSymbol = LayoutRoot.Resources["DefaultFillSymbol"] as FillSymbol
            };
            MyDrawSurface.DrawComplete += MyDrawSurface_DrawComplete;
        }

        private void esriTools_ToolbarItemClicked(object sender, ESRI.ArcGIS.Client.Toolkit.SelectedToolbarItemArgs e)
        {
            switch (e.Index)
            {
                case 0: // Point
                    MyDrawSurface.DrawMode = DrawMode.Point;                    
                    break;
                case 1: // Polyline
                    MyDrawSurface.DrawMode = DrawMode.Polyline;                    
                    break;
                case 2: // Polygon
                    MyDrawSurface.DrawMode = DrawMode.Polygon;                    
                    break;
                case 3: // Rectangle
                    MyDrawSurface.DrawMode = DrawMode.Rectangle;                    
                    break;
                default: // Clear
                    MyDrawSurface.DrawMode = DrawMode.None;
                    GraphicsLayer selectionGraphicslayer = MyMap.Layers["MySelectionGraphicsLayer"] as GraphicsLayer;
                    selectionGraphicslayer.ClearGraphics();
                    QueryDetailsDataGrid.ItemsSource = null;
                    ResultsDisplay.Visibility = Visibility.Collapsed;
                    break;
            }
            MyDrawSurface.IsEnabled = (MyDrawSurface.DrawMode != DrawMode.None);
            StatusTextBlock.Text = e.Item.Text;
        }

        private void MyDrawSurface_DrawComplete(object sender, ESRI.ArcGIS.Client.DrawEventArgs args)
        {
            GraphicsLayer selectionGraphicslayer = MyMap.Layers["MySelectionGraphicsLayer"] as GraphicsLayer;
            selectionGraphicslayer.ClearGraphics();

        

            QueryTask queryTask = new QueryTask((Layers.SelectedItem as FeatureLayer).Url);
            //... more code here
           

            queryTask.ExecuteCompleted += QueryTask_ExecuteCompleted;
            queryTask.Failed += QueryTask_Failed;


            // Bind data grid to query results
            Binding resultFeaturesBinding = new Binding("LastResult.Features");
            resultFeaturesBinding.Source = queryTask;
            QueryDetailsDataGrid.SetBinding(DataGrid.ItemsSourceProperty, resultFeaturesBinding);
            Query query = new ESRI.ArcGIS.Client.Tasks.Query();

            // Specify fields to return from query
            //query.OutFields.AddRange(new string[] { "STATE_NAME", "SUB_REGION", "STATE_FIPS", "STATE_ABBR", "POP2000", "POP2007" });
            //

            query.OutFields.Add("*");

            query.Geometry = args.Geometry;

            // Return geometry with result features
            query.ReturnGeometry = true;

            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;
            }

            GraphicsLayer graphicsLayer = MyMap.Layers["MySelectionGraphicsLayer"] as GraphicsLayer;

            if (featureSet != null && featureSet.Features.Count > 0)
            {
                foreach (Graphic feature in featureSet.Features)
                {
                    feature.Symbol = LayoutRoot.Resources["ResultsFillSymbol"] as FillSymbol;
                    graphicsLayer.Graphics.Insert(0, feature);
                }
                ResultsDisplay.Visibility = Visibility.Visible;
            }
            MyDrawSurface.IsEnabled = false;
        }

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

        private void GraphicsLayer_MouseEnter(object sender, GraphicMouseEventArgs args)
        {
                QueryDetailsDataGrid.Focus();
                QueryDetailsDataGrid.SelectedItem = args.Graphic;
                QueryDetailsDataGrid.CurrentColumn = QueryDetailsDataGrid.Columns[0];
                QueryDetailsDataGrid.ScrollIntoView(QueryDetailsDataGrid.SelectedItem, QueryDetailsDataGrid.Columns[0]);
        }

        private void GraphicsLayer_MouseLeave(object sender, GraphicMouseEventArgs args)
        {
                QueryDetailsDataGrid.Focus();
                QueryDetailsDataGrid.SelectedItem = null;
        }

        private void QueryDetailsDataGrid_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            foreach (Graphic g in e.AddedItems)
                g.Select();

            foreach (Graphic g in e.RemovedItems)
                g.UnSelect();
        }

        private void QueryDetailsDataGrid_LoadingRow(object sender, DataGridRowEventArgs e)
        {
            e.Row.MouseEnter += Row_MouseEnter;
            e.Row.MouseLeave += Row_MouseLeave;
        }

        void Row_MouseEnter(object sender, MouseEventArgs e)
        {
            (((System.Windows.FrameworkElement)(sender)).DataContext as Graphic).Select();
        }

        void Row_MouseLeave(object sender, MouseEventArgs e)
        {
            DataGridRow row = sender as DataGridRow;            
            Graphic g = ((System.Windows.FrameworkElement)(sender)).DataContext as Graphic;

            if (!QueryDetailsDataGrid.SelectedItems.Contains(g))
                g.UnSelect();
        }
    }   
}

Re: How to perform spatial query between two services...

JenniferNery — Thu, 21 Oct 2010 02:29:15 GMT

No problem. We learn a lot from the forum too 🙂

You missed:
private ObservableCollection<FeatureLayer> layers = new ObservableCollection<FeatureLayer>();

Re: How to perform spatial query between two services...

JMcNeil — Thu, 21 Oct 2010 17:38:15 GMT

Thanks Jennifer! With the help of another friend who pointed out that I did not need this code!

// Bind data grid to query results
            Binding resultFeaturesBinding = new Binding("LastResult.Features");
            resultFeaturesBinding.Source = queryTask;
            QueryDetailsDataGrid.SetBinding(DataGrid.ItemsSourceProperty, resultFeaturesBinding);
            Query query = new ESRI.ArcGIS.Client.Tasks.Query();

I finally got it working. Super Sweet. thanks for sticking with me and thanks to buddy Alan aka The Wolf!

As promised I'm going to do my best to help out a few lingering posts!

Thanks so much

Re: How to perform spatial query between two services...

DavidAshton — Sat, 11 Dec 2021 20:00:06 GMT

Jennifer and John,

Thanks for all the posts. This is exactly what I was looking for and I also got it implemented with this forum.

I have a quick question, which I was hoping Jennfier could answer.

If I'm populating my combo layers list with serveral layers that are either points, polys, and lines. How can set the right fill (SimpleLine, Fill, or Marker) and keep the interaction with the table/graphic (hover over, row click to highlight, etc.)

I can handle writing the VisualState Groups in xaml but as far as the code behind how should I change it.

It seems like I need to add a conditional statement in the foreach (Graphic feature in featureSet.Features) loop.....as you can see below I tired to just add a SimpleLineSymbol ref but it breaks my FillSymbol and all the interaction.


    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;
            }

            GraphicsLayer graphicsLayer = MyMap.Layers["MySelectionGraphicsLayer"] as GraphicsLayer;


            if (featureSet != null && featureSet.Features.Count > 0)

                ResultsDisplay.Visibility = Visibility.Visible;

            {
                foreach (Graphic feature in featureSet.Features)
                {
                    feature.Symbol = LayoutRoot.Resources["ResultsFillSymbol"] as FillSymbol;
                   

                    feature.Symbol = LayoutRoot.Resources["DefaultLineSymbol"] as SimpleLineSymbol;
                    graphicsLayer.Graphics.Insert(0, feature);

                }
              ResultsDisplay.Visibility = Visibility.Visible;
            }
            MyDrawSurface.IsEnabled = false;
        }

Thanks again!

Great Post!

Sincerely,
Dave Ashton

Re: How to perform spatial query between two services...

JMcNeil — Sat, 11 Dec 2021 20:00:09 GMT

Dave,

What about writing a switch statement....something like:

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;
            }

            GraphicsLayer graphicsLayer = Map.Layers["MySelectionGraphicsLayer"] as GraphicsLayer;

            if (featureSet != null && featureSet.Features.Count > 0)
            {
                

                foreach (Graphic feature in featureSet.Features)

                   
                {

                    switch (feature.Attributes["Shape"].ToString())
                    {
                        case "Polygon":
                            feature.Symbol = LayoutRoot.Resources["DefaultFillSymbol"] as FillSymbol;
                            break;
                        case "Polyline":
                            feature.Symbol = LayoutRoot.Resources["DefaultLineSymbol"] as SimpleMarkerSymbol;
                            break;
                        case "Point":
                            feature.Symbol = LayoutRoot.Resources["Default.MarkerSymbol"] as SimpleLineSymbol;
                            break;
                    }



                    graphicsLayer.Graphics.Insert(0, feature);

       
                }
                ResultsDisplay.Visibility = Visibility.Visible;
            }
            MyDrawSurface.IsEnabled = false;
        }

I'm not sure if that will work. I just copied Jen's code from above and add the switch there might be a few typos.

J.

Re: How to perform spatial query between two services...

DavidAshton — Sat, 11 Dec 2021 20:00:11 GMT

Dave,

What about writing a switch statement....something like:

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;
            }

            GraphicsLayer graphicsLayer = Map.Layers["MySelectionGraphicsLayer"] as GraphicsLayer;

            if (featureSet != null && featureSet.Features.Count > 0)
            {
                

                foreach (Graphic feature in featureSet.Features)

                   
                {

                    switch (feature.Attributes["Shape"].ToString())
                    {
                        case "Polygon":
                            feature.Symbol = LayoutRoot.Resources["DefaultFillSymbol"] as FillSymbol;
                            break;
                        case "Polyline":
                            feature.Symbol = LayoutRoot.Resources["DefaultLineSymbol"] as SimpleMarkerSymbol;
                            break;
                        case "Point":
                            feature.Symbol = LayoutRoot.Resources["Default.MarkerSymbol"] as SimpleLineSymbol;
                            break;
                    }



                    graphicsLayer.Graphics.Insert(0, feature);

       
                }
                ResultsDisplay.Visibility = Visibility.Visible;
            }
            MyDrawSurface.IsEnabled = false;
        }

I'm not sure if that will work. I just copied Jen's code from above and add the switch there might be a few typos.

J.

John,

Thanks for the reply, looks like there is no typos and I get no errors but now the query doesn't work. Nothing gets selected and nothing returns to the table? Any other suggestions.

Dave

Re: How to perform spatial query between two services...

JMcNeil — Sat, 11 Dec 2021 20:00:14 GMT

Oh, Jennifer is working with featureSet not Graphic what about commenting out this and adding


    // switch (feature.Attributes["Shape"].ToString())

 switch (feature.Geometry.ToString())

What does that do for you?