In some cases, you may want the component to use a data type dictionary that is different from what resides in the OPC server, or is not present in the OPC server at all. These situations may be, for example:

• The server vendor has intentionally omitted the data type dictionary from the OPC server due to performance and size constraints (small embedded devices).
• The server vendor has omitted the data type dictionary from the OPC server due to mistake or overlook.
• The OPC server contains the data type dictionary, but the dictionary does not match the actual data types and encoding.

Each data type dictionary is identified by the endpoint descriptor and node descriptor (data type dictionary ID) in the data type system. You can externally add or remove data type dictionaries from your code, identifying them by the data type dictionary ID.

Take following steps to add or remove the data type dictionary:

1. Get the IEasyUAClientComplexData Interface service from your EasyUAClient Class instance using the GetService Method.
2. Using the FindDataTypeSystem Method on the IEasyUAClientComplexData Interface, find the data type system you want to manipulate. Pass in the encoding name of the data type system, e.g. DefaultBinary Property.
3. Call the AddDataTypeDictionary Method or the RemoveDataTypeDictionary Method on the IUADataTypeSystem Interface.

Note that the data type system may only contain data type dictionaries that were previously referenced. Once the data type dictionary is added, be it from your code or otherwise, it stays there until removed. If your intent is to re-define an existing data type dictionary or define a data type dictionary that does not exist in the server, you need to add it to the data type system at the beginning, before an attempt tor etrieve it from the server is made.