ArchiveReader Component

Properties   Methods   Events   Config Settings   Errors  

The ArchiveReader component supports inspection and extraction of files from zip, tar, gzip and bzip2 archives.

Syntax

TsbxArchiveReader

Remarks

ArchiveReader shows and extracts archived files.

Property List

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The following is the full list of the properties of the component with short descriptions. Click on the links for further details.

Method List

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The following is the full list of the methods of the component with short descriptions. Click on the links for further details.

Event List

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The following is the full list of the events fired by the component with short descriptions. Click on the links for further details.

Config Settings

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The following is a list of config settings for the component with short descriptions. Click on the links for further details.

ArchiveType Property (ArchiveReader Component)

The type of the archive file.

Syntax

property ArchiveType: TsbxArchiveTypes read get_ArchiveType;

TsbxArchiveTypes = (
  aftUnknown,
  aftZip,
  aftGzip,
  aftBzip2,
  aftTar,
  aftTarGzip,
  aftTarBzip2,
  aftSFX
);

Default Value

aftUnknown

Remarks

Use this property to learn about the type (format) of the opened archive.

This property is read-only.

DecryptionCertificates Property (ArchiveReader Component)

A collection of decryption certificates.

Syntax

property DecryptionCertificates: TsbxCertificateList read get_DecryptionCertificates write set_DecryptionCertificates;

Remarks

Use this property to provide a collection of decryption certificates. All certificates should contain their respective private keys.

When processing an encrypted archive, the component will walk through the certificate list to locate the matching decryption certificate.

This property is not available at design time.

Please refer to the Certificate type for a complete list of fields.

DecryptionPassword Property (ArchiveReader Component)

The decryption password.

Syntax

property DecryptionPassword: String read get_DecryptionPassword write set_DecryptionPassword;

Default Value

''

Remarks

Use this property to provide the decryption password for the archive.

FileData Property (ArchiveReader Component)

The contents of the last extracted file.

Syntax

property FileData: TBytes read get_FileData write set_FileData;

Remarks

Use this property to get the contents of the last extracted file with DataSource set to stBuffer (2).

This property is not available at design time.

Files Property (ArchiveReader Component)

Lists all files contained in the archive.

Syntax

property Files: TsbxArchivedFileList read get_Files;

Remarks

Use this collection property to walk through the list of files contained in the archive. Use individual file entries to cherry-pick the files that should be extracted by adjusting their Action property, or fine-tune extraction paths using LocalPath property.

This property is read-only and not available at design time.

Please refer to the ArchivedFile type for a complete list of fields.

FIPSMode Property (ArchiveReader Component)

Reserved.

Syntax

property FIPSMode: Boolean read get_FIPSMode write set_FIPSMode;

Default Value

false

Remarks

This property is reserved for future use.

HashAlgorithm Property (ArchiveReader Component)

Returns the hash algorithm that was used to generate the signature.

Syntax

property HashAlgorithm: String read get_HashAlgorithm;

Default Value

''

Remarks

Check this property after calling Extract to get the hash algorithm which was used to calculate the signature.

This property is read-only and not available at design time.

KnownCertificates Property (ArchiveReader Component)

A collection of certificates to be used for signature validation.

Syntax

property KnownCertificates: TsbxCertificateList read get_KnownCertificates write set_KnownCertificates;

Remarks

Use this property to provide a list of certificates to be used for signature validation.

This property is not available at design time.

Please refer to the Certificate type for a complete list of fields.

Opened Property (ArchiveReader Component)

Indicates if the component is in the open state.

Syntax

property Opened: Boolean read get_Opened;

Default Value

false

Remarks

Use this property to check if the component provides access to an open archive file.

This property is read-only.

SignatureValidationResult Property (ArchiveReader Component)

The signature validation result.

Syntax

property SignatureValidationResult: TsbxSignatureValidities read get_SignatureValidationResult;

TsbxSignatureValidities = (
  svtValid,
  svtUnknown,
  svtCorrupted,
  svtSignerNotFound,
  svtFailure
);

Default Value

svtValid

Remarks

Use this property to check the result of the most recent signature validation.

This property is read-only and not available at design time.

SigningCertificate Property (ArchiveReader Component)

The certificate of the signature creator.

Syntax

property SigningCertificate: TsbxCertificate read get_SigningCertificate;

Remarks

Use this property to access the certificate that was used to create the signature.

This property is read-only and not available at design time.

Please refer to the Certificate type for a complete list of fields.

Close Method (ArchiveReader Component)

Closes the current archive.

Syntax

procedure Close();

Remarks

Use this method to close the archive that is currently opened and release the associated memory. You won't be able to extract files or access the archive details after closing the archive.

Config Method (ArchiveReader Component)

Sets or retrieves a configuration setting.

Syntax

function Config(ConfigurationString: String): String;

Remarks

Config is a generic method available in every component. It is used to set and retrieve configuration settings for the component.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

DoAction Method (ArchiveReader Component)

Performs an additional action.

Syntax

function DoAction(ActionID: String; ActionParams: String): String;

Remarks

DoAction is a generic method available in every component. It is used to perform an additional action introduced after the product major release. The list of actions is not fixed, and may be flexibly extended over time.

The unique identifier (case insencitive) of the action is provided in the ActionID parameter.

ActionParams contains the value of a single parameter, or a list of multiple parameters for the action in the form of PARAM1=VALUE1;PARAM2=VALUE2;....

Extract Method (ArchiveReader Component)

Extracts a single file from the archive.

Syntax

procedure Extract(Path: String; LocalPath: String; PreserveFullPath: Boolean);

Remarks

Use this method to extract a single file from the archive.

Pass the internal path to the entry in the archive via the Path parameter, and the path where to save the extracted entry via the LocalPath parameter. Set PreserveFullPath to true to enforce full-path extraction, in which case LocalPath would indicate the mount point at which the full Path needs to be rooted. If PreserveFullPath is false, the LocalPath provides the final location for the extracted file.

Use ExtractAll to extract all files at once.

ExtractAll Method (ArchiveReader Component)

Extract all the files contained in the archive.

Syntax

procedure ExtractAll(OutputPath: String; OverwriteExisting: Boolean);

Remarks

Use this method to extract all the files contained in the archive file. Pass the path where the extracted files should be saved via the OutputPath parameter. Existing files will be overwritten if the OverwriteExisting parameter is set to true.

You can cherry-pick the files to extract, as well as choose different extraction destinations (including files at custom locations, streams, or memory buffers) by subscribing to BeforeExtractFile and AfterExtractFile events.

Use Extract to extract a single file.

Open Method (ArchiveReader Component)

Opens an archive file.

Syntax

procedure Open(ArchiveType: Integer; ArchivePath: String);

Remarks

Call this method to open an archive file. Provide the archive type via the ArchiveType parameter, and the path via the ArchivePath parameter.

The following archive types (formats) are supported:

OpenBytes Method (ArchiveReader Component)

Loads an archive file from a byte array.

Syntax

procedure OpenBytes(ArchiveType: Integer; ArchiveBytes: TBytes);

Remarks

Call this method to load an archive file from a byte array. Provide the archive type via the ArchiveType parameter, and the byte array containing the archive data via the ArchiveBytes parameter.

The following archive types (formats) are supported:

OpenStream Method (ArchiveReader Component)

Loads an archive file from a stream.

Syntax

procedure OpenStream(ArchiveType: Integer; ArchiveStream: TStream);

Remarks

Call this method to load an archive file from a stream. Provide the archive type via the ArchiveType parameter, and the stream containing the archive data via the ArchiveStream parameter.

The following archive types (formats) are supported:

AfterExtractFile Event (ArchiveReader Component)

Marks the completion of extraction of an archived file.

Syntax

type TAfterExtractFileEvent = procedure (
  Sender: TObject;
  const Path: String;
  FileSize: Int64;
  DataSource: Integer
) of Object;

property OnAfterExtractFile: TAfterExtractFileEvent read FOnAfterExtractFile write FOnAfterExtractFile;

Remarks

Subscribe to this event to get notified about the completion of extraction of an archived file.

The Path parameter specifies the internal path to the entry inside the archive. The FileSize indicates the size of the decompressed file, and the DataSource specifies the type of the destination media.

BeforeExtractFile Event (ArchiveReader Component)

Marks the start of extraction of an archived file.

Syntax

type TBeforeExtractFileEvent = procedure (
  Sender: TObject;
  const Path: String;
  FileSize: Int64;
  var DataSource: Integer;
  var ExtractionPath: String;
  var Skip: Boolean
) of Object;

property OnBeforeExtractFile: TBeforeExtractFileEvent read FOnBeforeExtractFile write FOnBeforeExtractFile;

Remarks

Subscribe to this event to be notified about the start of extraction of an archived entry. The handler of this event is a good place to tune up the destination media.

The Path parameter indicates the path to the extracted entry in the archive. The FileSize specifies the uncompressed size of the file. Set the by-reference DataSource parameter in accordance with the desired extraction media type:

If saving to a stream or buffer, use AfterExtractFile to collect the extracted data from FileStream or FileData, and dispose of any objects allocated in this event handler (such as the output stream).

Use the Skip parameter to cancel extraction of this file and proceed to the next one.

DecryptionPasswordNeeded Event (ArchiveReader Component)

Requests a decryption password, when needed.

Syntax

type TDecryptionPasswordNeededEvent = procedure (
  Sender: TObject;
  const PasswordTarget: String;
  var Cancel: Boolean
) of Object;

property OnDecryptionPasswordNeeded: TDecryptionPasswordNeededEvent read FOnDecryptionPasswordNeeded write FOnDecryptionPasswordNeeded;

Remarks

Component fires this event when it needs a password to decrypt the archive. Subscribe to this event if you expect to process encrypted archives.

Inside the event handler, please assign the correct password to DecryptionPassword property, or set Cancel parameter to true to terminate the processing.

Error Event (ArchiveReader Component)

Reports information about errors during archive processing.

Syntax

type TErrorEvent = procedure (
  Sender: TObject;
  ErrorCode: Integer;
  const Description: String
) of Object;

property OnError: TErrorEvent read FOnError write FOnError;

Remarks

The event is fired in case of exceptional conditions during archive processing.

ErrorCode contains an error code and Description contains a textual description of the error.

Notification Event (ArchiveReader Component)

This event notifies the application about an underlying control flow event.

Syntax

type TNotificationEvent = procedure (
  Sender: TObject;
  const EventID: String;
  const EventParam: String
) of Object;

property OnNotification: TNotificationEvent read FOnNotification write FOnNotification;

Remarks

The component fires this event to let the application know about some event, occurrence, or milestone in the component. For example, it may fire to report completion of the document processing. The list of events being reported is not fixed, and may be flexibly extended over time.

The unique identifier of the event is provided in EventID parameter. EventParam contains any parameters accompanying the occurrence. Depending on the type of the component, the exact action it is performing, or the document being processed, one or both may be omitted.

Progress Event (ArchiveReader Component)

Reports the progress of data extraction.

Syntax

type TProgressEvent = procedure (
  Sender: TObject;
  Processed: Int64;
  Total: Int64;
  OverallProcessed: Int64;
  OverallTotal: Int64;
  var Cancel: Boolean
) of Object;

property OnProgress: TProgressEvent read FOnProgress write FOnProgress;

Remarks

Subscribe to this event to be notified about decompression progress.

Processed and Total report the progress of extraction of the current entry; OverallProcessed and OverallTotal report the progress of the whole operation. Set Cancel to true to stop the operation.

RecipientFound Event (ArchiveReader Component)

Informs the application that an archive is encrypted with a digital certificate.

Syntax

type TRecipientFoundEvent = procedure (
  Sender: TObject;
  RecipientHash: TBytes;
  CertFound: Boolean
) of Object;

property OnRecipientFound: TRecipientFoundEvent read FOnRecipientFound write FOnRecipientFound;

Remarks

The component fires this event when processing archives encrypted with an X.509 certificate. CertFound indicates whether the matching certificate has been found in DecryptionCertificates collection.

This event is an opportunity to add the decryption certificate on a later stage if it was not known at the start of the processing.

SignatureFound Event (ArchiveReader Component)

Signifies the start of signature validation.

Syntax

type TSignatureFoundEvent = procedure (
  Sender: TObject;
  const IssuerRDN: String;
  SerialNumber: TBytes;
  SubjectKeyID: TBytes;
  CertFound: Boolean;
  var ValidateSignature: Boolean;
  var ValidateChain: Boolean
) of Object;

property OnSignatureFound: TSignatureFoundEvent read FOnSignatureFound write FOnSignatureFound;

Remarks

This event tells the application that signature validation is about to start, and provides the details about the signer's certificate via its IssuerRDN, SerialNumber, and SubjectKeyID parameters. It fires for every signature located in the verified document or message.

The CertFound is set to True if the component has found the needed certificate in one of the known locations, and to False otherwise, in which case you must provide it manually via KnownCertificates property.

Signature validation consists of two independent stages: cryptographic signature validation and chain validation. Separate validation results are reported for each, with SignatureValidationResult and ChainValidationResult properties respectively.

Use the ValidateSignature and ValidateChain parameters to tell the verifier which stages to include in the validation.

ArchivedFile Type

Provides information about the compressed file.

Remarks

Use this type to access compressed file details.

Fields

Constructors

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constructor Create();

Creates a new ArchivedFile object.

Certificate Type

Provides details of an individual X.509 certificate.

Remarks

This type provides access to X.509 certificate details.

Fields

Constructors

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constructor Create();

Creates a new object with default field values.

Config Settings (ArchiveReader Component)

The component accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

ArchiveReader Config Settings

Base Config Settings

Trappable Errors (ArchiveReader Component)