IData can store any data object that is an instance of the Common Data Types, arrays with two or less dimensions, or instances of any class derived from System.Object. However, instances of custom classes may cause errors when used to invoke an integration service. Integration Server runs as a Java process; any custom objects passed to an integration service are meaningless because Integration Server does not have a definition of that class. The same holds true for services that attempt to return an instance of a custom Java class. The .NET client does not have a class definition with which to create the Java class.

The Client API includes the helper class IDataUtil for extracting variables from IData with common data types. For example, getString() extracts an object from an IData object and casts it as a String. Similar methods exist for integers, arrays, and so forth. For further details, see the IDataUtil class documentation as explained in Microsoft .NET Client API Documentation.

Output variables that are native arrays are retrieved from the output IData as System.Array instances, not as their native array type. For example, input data can be entered as a native array type:

However, when retrieved from IData, the array is of type System.Array.