Class: OpcPackage

An OPC package loaded from .pptx bytes.

Fidelity contract: parts that are never mutated (Part.markDirty()) are written back byte-identically by save(). Whole-zip byte-identity is not promised (zip metadata and compression may differ), but part bodies, the part-name set, and part order are preserved.

Properties

contentTypes

readonly contentTypes: ContentTypes

Content-type resolution + registration overlay.

Accessors

parts

Get Signature

get parts(): ReadonlyMap<string, Part>

All parts, keyed by partname, in zip/add order.

Returns

ReadonlyMap<string, Part>

Methods

addPart()

addPart(partName, contentType, bytes): Part

Add a new part and register its content type (ensureRegistered), so the package stays consistent. Throws if the partname is already taken.

Parameters

Parameter	Type
partName	string
contentType	string
bytes	Uint8Array

Returns

Part

---

part()

part(partName): Part | undefined

The part at partName, or undefined. Takes null, as a part-name getter such as Picture.imagePartName reads when there is no part to name, and misses on it.

Parameters

Parameter	Type
partName	string | null

Returns

Part | undefined

---

partsByContentType()

partsByContentType(contentType): Part[]

Parameters

Parameter	Type
contentType	string

Returns

Part[]

---

relationshipsFor()

relationshipsFor(sourcePartName?): Relationships

Relationships owned by a part ('/' for the package-level /_rels/.rels). Parts without a .rels part get an empty set.

Parameters

Parameter	Type	Default value
sourcePartName	string	'/'

Returns

Relationships

---

removePart()

removePart(partName): boolean

Remove a part and return whether it existed. Its .rels part goes with it, along with its Override content-type registration and any cached relationship set it owned, so a later save() neither re-emits it nor flushes a stale .rels for it. A relationship set belongs to its part: one left behind would come back as the relationships of the next part added under the same name. Low-level: it does not touch references to this part (dangling rels are the caller's concern) nor cascade to parts this one referenced; see Presentation.removeSlide for the slide-aware variant that unwires the presentation and prunes orphans.

Parameters

Parameter	Type
partName	string

Returns

boolean

---

reserveMediaPartName()

reserveMediaPartName(extension, base?): string

Reserve an unused media partname /ppt/media/<base><n>.<ext> (n one past the highest existing index for that base). Does not create the part.

Parameters

Parameter	Type	Default value
extension	string	undefined
base	string	'image'

Returns

string

---

reservePartNameLike()

reservePartNameLike(templatePartName, taken?): string

Reserve an unused partname in the same directory and naming family as templatePartName, with a fresh index one past the highest existing one. The template's filename is split into a base (its stem minus any trailing digits) and an extension, e.g. /ppt/slideLayouts/slideLayout1.xml → /ppt/slideLayouts/slideLayout<n>.xml, /ppt/media/image1.png → /ppt/media/image<n>.png. Used when copying a part in from another package. Does not create the part.

taken names partnames to count as existing although the package does not hold them yet: an import plan's names for the parts it would add, so the names it predicts are the ones the copy itself is then given.

Parameters

Parameter	Type
templatePartName	string
taken?	ReadonlySet<string>

Returns

string

---

save()

save(): Promise<Uint8Array<ArrayBufferLike>>

Re-emit the package. Clean parts are written from their original bytes; dirty parts from their DOM. Dirty relationship sets and content types are flushed first. Part order is preserved from load; added parts append.

Returns

Promise<Uint8Array<ArrayBufferLike>>

---

load()

static load(input): Promise<OpcPackage>

Parameters

Parameter	Type
input	OpcInput

Returns

Promise<OpcPackage>