EnumFormatEtc

EnumFormatEtc is a function in the Microsoft COM (Component Object Model) API used for enumerating supported data formats for a given data object. It is typically used in conjunction with clipboard operations or drag-and-drop functionality to determine which data formats a COM object can provide. The function retrieves information about available data formats, such as their names and media types, and allows applications to query for specific format details.

The EnumFormatEtc function is part of the IEnumFORMATETC interface. It takes a pointer to an array of FORMATETC structures as input, along with parameters to control the enumeration process, such as the number of formats to retrieve and the desired type of format information. The FORMATETC structure itself contains details about a specific data format, including its aspect (e.g., content or icon), medium (e.g., clipboard, file, or metafile), and format identifier.

By iterating through the results returned by EnumFormatEtc, applications can dynamically discover and present available data transfer options to the user. This enables flexible data exchange between different applications and COM objects, ensuring that data can be represented and transferred in a format that is mutually understood. The function is crucial for implementing robust data interoperability within the COM framework.