Use this property to specify the position that an OPC Block Element occupies among the OPC Block Elements configured in the OPC Block's Size property where it is inserted. This property's accepts values from 0 (zero) to a value less than the value defined in Size. For example, configuring an OPC Block's Size property to 20, the maximum valid number for this property is 19 and the minimum is 0 (zero). This property can be changed after starting communication. Default value of this property is 0 (zero), but when mapping OPC Block Elements of an OPC Block, Elipse E3 Studio automatically sets this property to the specified value. The next script contains an example of using this property.

Sub Element1_OnRead()
  MsgBox Index
End Sub