public void ReadAsset(Asset asset)
{
   // Get the asset name, type and library name.
   AssetType type = asset.AssetType;
   string name = asset.Name;
   string libraryName = asset.LibraryName;

   // travel the asset properties in the asset.
   for (int idx = 0; idx < asset.Size; idx++)
   {
      AssetProperty prop = asset[idx];
      ReadAssetProperty(prop);
   }
}

public void ReadAssetProperty(AssetProperty prop)
{
   switch (prop.Type)
   {
      // Retrieve the value from simple type property is easy.
      // for example, retrieve bool property value.
      case AssetPropertyType.APT_Boolean:
         AssetPropertyBoolean boolProp = prop as AssetPropertyBoolean;
         bool propValue = boolProp.Value;
         break;

      // When you retrieve the value from the data array property,
      // you may need to get which value the property stands for.
      // for example, the APT_Double44 may be a transform data.
      case AssetPropertyType.APT_Double44:
         AssetPropertyDoubleArray4d transformProp = prop as AssetPropertyDoubleArray4d;
         Autodesk.Revit.DB.DoubleArray tranformValue = transformProp.Value;
         break;

      // The APT_List contains a list of sub asset properties with same type.
      case AssetPropertyType.APT_List:
         AssetPropertyList propList = prop as AssetPropertyList;
         IList<AssetProperty> subProps = propList.GetValue();
         if (subProps.Count == 0)
            break;
         switch (subProps[0].Type)
         {
            case AssetPropertyType.APT_Integer:
               foreach (AssetProperty subProp in subProps)
               {
                  AssetPropertyInteger intProp = subProp as AssetPropertyInteger;
                  int intValue = intProp.Value;
               }
               break;
         }
         break;

      case AssetPropertyType.APT_Asset:
         Asset propAsset = prop as Asset;
         ReadAsset(propAsset);
         break;
      default:
         break;
   }

   // Get the connected properties.
   // please notice that the information of many texture stores here.
   if (prop.NumberOfConnectedProperties == 0)
      return;
   foreach (AssetProperty connectedProp in prop.GetAllConnectedProperties())
   {
      // Note: Usually, the connected property is an Asset.
      ReadAssetProperty(connectedProp);
   }
}

Public Sub ReadAsset(asset As Asset)
    ' Get the asset name, type and library name.
    Dim type As AssetType = asset.AssetType
    Dim name As String = asset.Name
    Dim libraryName As String = asset.LibraryName

    ' travel the asset properties in the asset.
    For idx As Integer = 0 To asset.Size - 1
        Dim prop As AssetProperty = asset(idx)
        ReadAssetProperty(prop)
    Next
End Sub

Public Sub ReadAssetProperty(prop As AssetProperty)
    Select Case prop.Type
        ' Retrieve the value from simple type property is easy.
        ' for example, retrieve bool property value.
        Case AssetPropertyType.APT_Boolean
            Dim boolProp As AssetPropertyBoolean = TryCast(prop, AssetPropertyBoolean)
            Dim propValue As Boolean = boolProp.Value
            Exit Select

            ' When you retrieve the value from the data array property,
            ' you may need to get which value the property stands for.
            ' for example, the APT_Double44 may be a transform data.
        Case AssetPropertyType.APT_Double44
            Dim transformProp As AssetPropertyDoubleArray4d = TryCast(prop, AssetPropertyDoubleArray4d)
            Dim tranformValue As Autodesk.Revit.DB.DoubleArray = transformProp.Value
            Exit Select

            ' The APT_List contains a list of sub asset properties with same type.
        Case AssetPropertyType.APT_List
            Dim propList As AssetPropertyList = TryCast(prop, AssetPropertyList)
            Dim subProps As IList(Of AssetProperty) = propList.GetValue()
            If subProps.Count = 0 Then
                Exit Select
            End If
            Select Case subProps(0).Type
                Case AssetPropertyType.APT_Integer
                    For Each subProp As AssetProperty In subProps
                        Dim intProp As AssetPropertyInteger = TryCast(subProp, AssetPropertyInteger)
                        Dim intValue As Integer = intProp.Value
                    Next
                    Exit Select
            End Select
            Exit Select

        Case AssetPropertyType.APT_Asset
            Dim propAsset As Asset = TryCast(prop, Asset)
            ReadAsset(propAsset)
            Exit Select
        Case Else
            Exit Select
    End Select

    ' Get the connected properties.
    ' please notice that the information of many texture stores here.
    If prop.NumberOfConnectedProperties = 0 Then
        Return
    End If
    For Each connectedProp As AssetProperty In prop.GetAllConnectedProperties()
        ' Note: Usually, the connected property is an Asset.
        ReadAssetProperty(connectedProp)
    Next
End Sub