Class AcDbBlockTableRecord

Base class for all symbol table records.

This class provides the fundamental functionality for all symbol table records, including name management and common attributes. Symbol table records represent entries in various symbol tables such as layer tables, linetype tables, text style tables, etc.

Example

class MySymbolTableRecord extends AcDbSymbolTableRecord<MySymbolTableRecordAttrs> {
  constructor(attrs?: Partial<MySymbolTableRecordAttrs>) {
    super(attrs);
  }
}

Hierarchy (View Summary)

Constructors

constructor

Properties

MODEL_SPACE_NAME PAPER_SPACE_NAME_PREFIX

Accessors

attrs blockInsertUnits blockScaling database explodability extensionDictionary flags isModelSapce isOverlayReference isPaperSapce isTemp isUnresolvedXref isXref layoutId name objectId origin ownerId pathName previewIcon

Methods

appendEntity assertOpenForWrite assignDatabase clone clonePreservingIdentity close createExtensionDictionary dxfIn dxfInControlString dxfInFields dxfInXData dxfOut dxfOutBlockBegin dxfOutBlockEnd dxfOutBlockRecord dxfOutFields dxfOutXData getAttr getAttrWithoutException getIdAt getXData newIterator removeEntity removeXData restoreFrom setAttr setXData isModelSapceName isPaperSapceName sanitizeImportedFlags

Constructors

constructor

Properties

StaticMODEL_SPACE_NAME

MODEL_SPACE_NAME: string = '*Model_Space'

Name constant for model space block table record

StaticPAPER_SPACE_NAME_PREFIX

PAPER_SPACE_NAME_PREFIX: string = '*Paper_Space'

Name prefix for paper space block table records

Accessors

attrs

blockInsertUnits

blockScaling

database

  • get database(): AcDbDatabase

  • Gets the database in which this object is resident.

    When an object isn't added to a database, this property returns the current working database. After it is added to a database, it will be set automatically. You should never set this value manually.

    Returns AcDbDatabase

    The database this object belongs to

    Example

    const db = obj.database;
  • set database(db: AcDbDatabase): void

  • Sets the database for this object.

    This is typically set automatically when the object is added to a database. Manual setting should be avoided unless you know what you're doing.

    Parameters

    Returns void

    Example

    obj.database = myDatabase;

explodability

extensionDictionary

  • get extensionDictionary(): undefined | string

  • Gets the objectId of the extension dictionary owned by this object.

    If the object does not have an extension dictionary, this returns undefined.

    In ObjectARX terms, this is equivalent to AcDbObject::extensionDictionary().

    Returns undefined | string

    The extension dictionary objectId, or undefined

    Example

    const dictId = obj.extensionDictionary
    if (dictId) {
      console.log('Has extension dictionary:', dictId)
    }
  • set extensionDictionary(value: undefined | string): void

  • Sets the objectId of the extension dictionary owned by this object.

    This does not create or delete the dictionary object itself ??it only establishes or clears the ownership relationship.

    Passing undefined removes the association.

    Parameters

    • value: undefined | string

      The extension dictionary objectId, or undefined

    Returns void

    Example

    obj.extensionDictionary = dict.objectId

flags

isModelSapce

  • get isModelSapce(): boolean

  • Returns true if this is a model space block table record.

    Model space is the primary drawing area where most entities are created.

    Returns boolean

    True if this is a model space block table record

    Example

    if (blockRecord.isModelSapce) {
      console.log('This is model space');
    }

isOverlayReference

isPaperSapce

  • get isPaperSapce(): boolean

  • Returns true if this is a paper space block table record.

    Paper space is used for creating layouts for printing and plotting.

    Returns boolean

    True if this is a paper space block table record

    Example

    if (blockRecord.isPaperSapce) {
      console.log('This is paper space');
    }

isTemp

  • get isTemp(): any

  • Returns true if this object is temporary and not yet committed to the database.

    A temporary object is identified by its objectId starting with the TEMP prefix.

    Returns any

isUnresolvedXref

  • get isUnresolvedXref(): boolean

  • True when this is an xref whose content has not been loaded into the block.

    File importers clear the Resolved bit via sanitizeImportedFlags because AutoCAD often writes Resolved even though web converters do not bind xref geometry. Runtime loaders (for example XATTACH) may set Resolved once an overlay session is available, even when the BTR stays empty.

    Returns boolean

isXref

layoutId

  • get layoutId(): string

  • Gets or sets the object ID of the associated AcDbLayout object in the Layouts dictionary.

    This property links the block table record to its corresponding layout object, which defines the viewport configuration and display settings for the block. For model space blocks, this is typically empty, while paper space blocks have a corresponding layout ID.

    Returns string

    The object ID of the associated layout

    Example

    const layoutId = blockRecord.layoutId;
    blockRecord.layoutId = 'some-layout-object-id';
  • set layoutId(value: string): void

  • Parameters

    • value: string

    Returns void

name

objectId

  • get objectId(): string

  • Gets the object ID.

    AutoCAD uses 64-bit integers to represent handles, which exceed the maximum integer value of JavaScript. Therefore, strings are used to represent object handles.

    Returns string

    The object ID as a string

    Example

    const id = obj.objectId;
    console.log(`Object ID: ${id}`);
  • set objectId(value: string): void

  • Sets the object ID.

    Parameters

    • value: string

      The new object ID

    Returns void

    Example

    obj.objectId = 'new-object-id';

origin

ownerId

  • get ownerId(): string

  • Gets the object ID of the owner of this object.

    Returns string

    The owner object ID

    Example

    const ownerId = obj.ownerId;
  • set ownerId(value: string): void

  • Sets the object ID of the owner of this object.

    Parameters

    • value: string

      The new owner object ID

    Returns void

    Example

    obj.ownerId = 'parent-object-id';

pathName

previewIcon

  • get previewIcon(): undefined | Uint8Array

  • Gets or sets the PreviewIcon binary payload for this block definition.

    Corresponds to AutoCAD .NET BlockTableRecord.PreviewIcon and DXF BLOCK_RECORD group code 310. The payload is typically a DIB (BITMAPINFO + bits), not a full BMP file. Stored as raw bytes to avoid hex doubling.

    Returns undefined | Uint8Array

    Preview icon bytes, or undefined when none exist

  • set previewIcon(value: undefined | Uint8Array): void

  • Parameters

    • value: undefined | Uint8Array

    Returns void

Methods

appendEntity

  • appendEntity(entity: AcDbEntity | AcDbEntity[]): void

  • Appends the specified entity or entities to this block table record.

    This method adds an entity to the block and sets up the necessary relationships between the entity and the block table record.

    Parameters

    Returns void

    Example

    const line = new AcDbLine();
    blockRecord.appendEntity(line);

ProtectedassertOpenForWrite

ProtectedassignDatabase

clone

clonePreservingIdentity

close

  • close(): void

  • Closes the object.

    All changes made to the object since it was opened are committed to the database, and a "closed" notification is sent. This method can be overridden by subclasses to provide specific cleanup behavior.

    Returns void

    Example

    obj.close();

createExtensionDictionary

  • createExtensionDictionary(): undefined | string

  • Creates the extension dictionary for this object if it does not already exist.

    This method closely mirrors the behavior of AcDbObject::createExtensionDictionary() in ObjectARX.

    • If the object already owns an extension dictionary, no new dictionary is created and the existing dictionary's objectId is returned.
    • Otherwise, a new AcDbDictionary is created, added to the same database, owned by this object, and its objectId is stored on this object.

    Returns undefined | string

    The objectId of the extension dictionary

    Example

    const dictId = obj.createExtensionDictionary()

dxfIn

  • dxfIn(filer: AcDbDxfFiler): this

  • Reads this object from a DXF filer (ObjectARX dxfIn).

    Reads common handle/owner fields, then delegates to dxfInFields. XData (group 1001+) is consumed when present after object fields.

    Group-102 control strings ({ACAD_XDICTIONARY, {ACAD_REACTORS, …) are consumed here so subclass readers still see handle/owner/subclass markers that follow them. Many real DXF writers emit these blocks on LAYER and entity records; skipping them would leave name/layer unset.

    Parameters

    Returns this

ProtecteddxfInControlString

dxfInFields

  • dxfInFields(filer: AcDbDxfFiler): this

  • Reads object-specific DXF fields (ObjectARX dxfInFields).

    Subclasses should override, call super.dxfInFields(filer) first when appropriate, then consume their subclass marker and fields in an order-independent loop.

    Per the AutoCAD DXF specification, readers must ignore undefined group codes and must not assume field order. Within a subclass loop the correct unknown-code behavior is break (skip and continue). Use pushBackItem only to hand a group-100 subclass marker (or XData) to another reader — never to abort on an unrecognized optional code.

    Parameters

    Returns this

ProtecteddxfInXData

dxfOut

dxfOutBlockBegin

dxfOutBlockEnd

dxfOutBlockRecord

dxfOutFields

ProtecteddxfOutXData

getAttr

  • getAttr(attrName: string): any

  • Gets the value of the specified attribute.

    This method will throw an exception if the specified attribute doesn't exist. Use getAttrWithoutException() if you want to handle missing attributes gracefully.

    Parameters

    • attrName: string

      The name of the attribute to retrieve

    Returns any

    The value of the specified attribute

    Throws

    When the specified attribute doesn't exist

    Example

    try {
      const value = obj.getAttr('objectId');
    } catch (error) {
      console.error('Attribute not found');
    }

getAttrWithoutException

  • getAttrWithoutException(attrName: string): any

  • Gets the value of the specified attribute without throwing an exception.

    This method returns undefined if the specified attribute doesn't exist, making it safer for optional attributes.

    Parameters

    • attrName: string

      The name of the attribute to retrieve

    Returns any

    The value of the specified attribute, or undefined if it doesn't exist

    Example

    const value = obj.getAttrWithoutException('optionalAttribute');
    if (value !== undefined) {
      // Use the value
    }

getIdAt

getXData

  • getXData(appId: string): undefined | AcDbResultBuffer

  • Retrieves the XData associated with this object for a given application ID.

    Extended Entity Data (XData) allows applications to attach arbitrary, application-specific data to an AcDbObject. Each XData entry is identified by a registered application name (AppId) and stored as an AcDbResultBuffer.

    This method is conceptually equivalent to AcDbObject::xData() in ObjectARX, but simplified to return the entire result buffer for the specified AppId.

    Parameters

    • appId: string

      The application ID (registered AppId name) that owns the XData

    Returns undefined | AcDbResultBuffer

    The AcDbResultBuffer associated with the AppId, or undefined if no XData exists for that AppId

    Example

    const xdata = obj.getXData('MY_APP')
    if (xdata) {
      // Read values from the result buffer
    }

newIterator

removeEntity

  • removeEntity(objectId: string | string[]): boolean

  • Removes the specified entity or entities from this block table record.

    Notes: Please call method AcDbEntity.erase to remove one entity instead of calling this function.

    AutoCAD ObjectARX API doesn't provide such one method to remove entities from the block table record. I guess it is done by friend class or function feature in C++. However, there are no similar feature in TypeScript. So we have to expose such one public method in AcDbBlockTableRecord.

    Parameters

    • objectId: string | string[]

      The object id or ids of entities to remove from this block table record

    Returns boolean

    ??true if an entity in the block table record existed and has been removed, or false if the entity does not exist.

removeXData

  • removeXData(appId: string): void

  • Removes the XData associated with the specified application ID.

    After removal, calls to getXData() for the same AppId will return undefined. If no XData exists for the given AppId, this method has no effect.

    This mirrors the behavior of clearing XData for a specific application in ObjectARX rather than removing all XData from the object.

    Parameters

    • appId: string

      The application ID whose XData should be removed

    Returns void

    Example

    obj.removeXData('MY_APP')

restoreFrom

setAttr

setXData

  • setXData(resbuf: AcDbResultBuffer): void

  • Attaches or replaces XData for this object.

    If XData already exists for the given AppId, it is replaced by the provided AcDbResultBuffer. The caller is responsible for ensuring that:

    • The AppId is registered in the database's AppId table
    • The result buffer follows valid DXF/XData conventions (e.g. starts with a 1001 group code for the AppId)

    This method is conceptually similar to AcDbObject::setXData() in ObjectARX.

    Parameters

    Returns void

    Example

    const rb = new AcDbResultBuffer([
      { code: AcDbDxfCode.ExtendedDataRegAppName, value: 'MY_APP' },
      { code: AcDbDxfCode.ExtendedDataAsciiString, value: 'custom value' }
    ])

    obj.setXData('MY_APP', rb)

StaticisModelSapceName

  • isModelSapceName(name: string): boolean

  • Returns true if the specified name is the name of the model space block table record.

    Model space is the primary drawing area where most entities are created.

    Parameters

    • name: string

      The name of one block table record.

    Returns boolean

    True if the specified name is the name of the model space block table record.

    Example

    if (AcDbBlockTableRecord.isModelSapceName('*Model_Space')) {
      console.log('This is the name of the model space block table record.');
    }

StaticisPaperSapceName

  • isPaperSapceName(name: string): boolean

  • Returns true if the specified name is the name of a paper space block table record.

    Paper space is used for creating layouts for printing and plotting.

    Parameters

    • name: string

      The name of one block table record.

    Returns boolean

    True if the specified name is the name of a paper space block table record.

    Example

    if (AcDbBlockTableRecord.isPaperSapceName('*Paper_Space1')) {
      console.log('This is the name of the paper space block table record.');
    }

StaticsanitizeImportedFlags

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