`pdfSetOCGContUsage`

Set the /Usage (application) dictionary fields for a layer —

Category	Optional content

Purpose — Set the /Usage (application) dictionary fields for a layer — how it should behave under View/Print/Export intents and its /CreatorInfo.

Description — Fields left at -1/empty in Value are not changed (this call only overwrites fields you explicitly set — call pdfInitOCGContUsage first so untouched fields stay -1). UserNameA/UserNameW, when non-empty, are appended to a per-OCG list rather than replacing a single value — repeated calls accumulate multiple /User /Name entries for the same OCG (see pdfGetOCGUsageUserName to enumerate them all; pdfGetOCGContUsage only ever surfaces the first one).

Declarations

BOOL32 __stdcall pdfSetOCGContUsage(PPDF IPDF, uint32_t Handle, TPDFOCGContUsage* Value);

Delphi

function pdfSetOCGContUsage(const IPDF: PPDF; Handle: Cardinal; var Value: TPDFOCGContUsage): LongBool; stdcall; external 'LumasPdf.dll';

Parameters

Parameter	Type	Description
`IPDF`	`PPDF`	Instance handle.
`Handle`	`Cardinal`	OCG handle.
`Value`	`TPDFOCGContUsage*`	Fields to apply; `-1`/empty fields are left unchanged.

Return value — TRUE on success; FALSE if Handle is out of range.

See also — pdfGetOCGContUsage, pdfGetOCGUsageUserName

C# (P/Invoke)

wrappers/dotnet/LumasPdf.cs

[return: MarshalAs(UnmanagedType.Bool)]

Area

Core SDK