topic Re: FeatureLayer in CodeBehind (C#) in ArcGIS API for Silverlight Questions

FeatureLayer in CodeBehind (C#)

UlfGrimhardt — Tue, 15 Feb 2011 12:22:34 GMT

Hi

Can anyone tell me how to create a FeatureLayer in CodeBehind?
I also need to implement a Where-Clause in my FeatureLayer and dont no how to do that either.
Additionally i would like to know if it is possible to dynamically add Values to the Where Clause.

For Examaple:
FeatureLayer.Where = Number = XY OR Number = XYZ

Somehow like this i think the normal way would be. But i have a List with lots of Numbers and i would like to add a Graphic to every Feature with an entry in that List.

Thanks in Advance!

Re: FeatureLayer in CodeBehind (C#)

JenniferNery — Sat, 11 Dec 2021 13:37:51 GMT

The following XAML-code

            <esri:FeatureLayer ID="MyFeatureLayer"
                    Url="http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Specialty/ESRI_StatesCitiesRivers_USA/MapServer/0" 
                    Where="POP1990 > 100000" />

is equivalent to:

 double number = 100000;
 FeatureLayer l = new FeatureLayer()
 {
  ID = "MyFeatureLayer",
  Url = "http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Specialty/ESRI_StatesCitiesRivers_USA/MapServer/0",
  Where = string.Format("POP1990 > {0}", number)
 };
 MyMap.Layers.Add(l);

You can use string.Format() with a number argument.

Re: FeatureLayer in CodeBehind (C#)

UlfGrimhardt — Sat, 11 Dec 2021 13:37:53 GMT

Ok thanks for your answer!

I tried the following code but always get error. Whats wrong with the "Where" part?

        private void btn_phoehe_Click(object sender, RoutedEventArgs e)
        {
            FeatureLayer l = new FeatureLayer()
            {
                ID = "MyFeatureLayer",
                Url = "http://XXXX/ArcGIS/rest/services/Test/MapServer/0",
                Where = "Name=Peter"            };
            map.Layers.Add(l);
        }

Re: FeatureLayer in CodeBehind (C#)

UlfGrimhardt — Wed, 16 Feb 2011 09:20:38 GMT

Ok i got it.

But is it possible to Filter for all Features that are part of a Array?
I have an Array with 20 Numbers. Now i would like to Filter for only those Features, whose Name is equal to the Numbers in my Array.

Re: FeatureLayer in CodeBehind (C#)

JenniferNery — Sat, 11 Dec 2021 13:37:56 GMT

Your Where clause would be something like

fcode in (10201, 11201)

where fcode is field name and 10201 and 11201 are elements of your number array.

You can use the following conversion from array to comma-delimited string.

int[] numbers = new int[] { 10201, 11201 };
string where = string.Format("fcode in ({0})", string.Join(",", Array.ConvertAll(numbers, i => i.ToString())));