`pdfLoadLayerConfig`

Apply an alternate configuration's layer visibility to the

Category	Optional content

Purpose — Apply an alternate configuration's layer visibility to the document's *current* (working) OCG visibility state.

Description — Index=0 restores every OCG to the visibility it had when created via pdfCreateOCG (the default /D config). Index >= 1 applies a named config created via pdfCreateOCLayerConfig — note the off-by-one: Index here is a config-*index* (Index-1 is the 0-based slot into the config array), whereas pdfCreateOCLayerConfig returns a 1-based config-*handle*. In practice they are numerically the same value for a config created immediately after CreateOCLayerConfig returns N: pass N as Index to load it. For that config, every OCG first takes the config's /BaseState, then explicit per-OCG ON overrides are applied, then explicit OFF overrides (pdfSetOCGConfigState) — OFF wins if an OCG is marked in both arrays for the same config (should not normally occur, since SetOCGConfigStateH always writes both arrays consistently as mutually exclusive).

Declarations

BOOL32 __stdcall pdfLoadLayerConfig(PPDF IPDF, int32_t Index);

Delphi

function pdfLoadLayerConfig(const IPDF: PPDF; Index: Integer): LongBool; stdcall; external 'LumasPdf.dll';

Parameters

Parameter	Type	Description
`IPDF`	`PPDF`	Instance handle.
`Index`	`Integer`	`0` = default config; `1..configCount` = a named config.

Return value — TRUE on success; FALSE if there are no OCGs, or Index is out of range for a named config.

See also — pdfCreateOCLayerConfig, pdfGetLayerConfig

C# (P/Invoke)

wrappers/dotnet/LumasPdf.cs

[return: MarshalAs(UnmanagedType.Bool)]

Area

Core SDK