[GIS] How to create a new feature layer from the selected features

arcobjects

I have a simple tool written in ArcObjects which takes features from a layer and does some processing on them.

I use a feature cursor to loop through all the features in the layer. To perform the necessary processing I have written several functions which accept an IFeatureLayer reference.

What I want to achieve is:

I want to process only those features which are selected
I don't want to change my code in all my existing functions. So I want to be able to continue to pass an IFeatureLayer reference to these functions.

How can I do this?

Best Answer

Query interface/cast from your original IFeatureLayer reference to IFeatureLayerDefinition and call its CreateSelectionLayer() method.

This will create a new feature layer from the existing feature layer based on its selection and optionally an expression to further filter it.

Related Solutions

[GIS] How to get all fields of selected features in C#

Are you sure the value of the field isn't null? What about:

if (!x.Equals(-1))
{
  object value = pfeat.get_Value(x);
  list.Add(value == null ? null : value.ToString());
}

I'm not sure if you want to inline the null test, you could always do:

if (!x.Equals(-1))
{
  object value = pfeat.get_Value(x);
  if(value != null)
  {
    list.Add(value.ToString());
  }
  else
  {
    list.Add(null);
  }
}

[GIS] ArcObjects .NET – How to close/release FeatureClass, Workspace, Factory

You have already covered many aspects in your post. However to expand on your question, always follow this pattern:

if (obj!=null)
ESRI.ArcGIS.ADF.ComReleaser.ReleaseCOMObject(obj);

obj = null;

Then call System.GC.Collect() to force the garbage collector to remove any references to the DBMS.

The order of release have to be Cursors, Features (IFeature), FeatureClasses, Workspaces and other ArcObjects instantiated.

ArcGIS Desktop and ArcEngine application are STA (single threaded application). It is neither safe nor advised to use ArcObjects across threads (Workers); One can use serialization and deserialization of objects to achieve this. For further details, take a look at here.

Best Answer

Related Solutions

[GIS] How to get all fields of selected features in C#

[GIS] ArcObjects .NET – How to close/release FeatureClass, Workspace, Factory

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