PDFDecrypt Component

Properties   Methods   Events   Config Settings   Errors  

The PDFDecrypt component decrypts PDF documents.

Syntax

TispPDFDecrypt

Remarks

The PDFDecrypt component supports decryption of both password-encrypted and certificate-encrypted PDF documents. To determine the document's encryption type before decrypting it, subscribe to the Password and RecipientInfo events and open the document. For example: pdfdecrypt.InputFile = "encrypted.pdf"; pdfdecrypt.OnPassword += (s, e) => { Console.WriteLine("The PDF document is encrypted with a password."); }; pdfdecrypt.OnRecipientInfo += (s, e) => { Console.WriteLine("The PDF document is encrypted with a certificate."); }; pdfdecrypt.Open(); pdfdecrypt.Close();

Password-Based Decryption

If you have determined that the PDF is encrypted with a password (or know that fact beforehand), you must provide the correct decryption password via the Password property (for user passwords) or the OwnerPassword configuration setting (for owner passwords) in order to decrypt the document and get access to its contents.

The following code shows how to decrypt a password-encrypted PDF document: pdfdecrypt.InputFile = "password_encrypted.pdf"; pdfdecrypt.OutputFile = "decrypted.pdf"; pdfdecrypt.Password = "password"; pdfdecrypt.Decrypt(); Alternatively, set the decryption password within your Password event handler, and the component will decrypt the document all the same. The Available parameter may come in handy in determining whether the component already possesses the necessary decryption password.

Certificate-Based Decryption

If you have determined that the PDF is encrypted with a certificate (or know that fact beforehand), you must provide the decryption certificate containing the correct private key in order to decrypt the document and get access to its contents.

The following code shows how to decrypt a certificate-encrypted PDF document: pdfdecrypt.InputFile = "cert_encrypted.pdf"; pdfdecrypt.OutputFile = "decrypted.pdf"; pdfdecrypt.DecryptionCert = new Certificate(CertStoreTypes.cstPFXFile, "C:/MyCerts/cert.pfx", "cert_pass", "*"); pdfdecrypt.Decrypt(); Alternatively, set the decryption certificate within your RecipientInfo event handler, and the component will decrypt the document all the same. Like in the Password event, the Available parameter may come in handy in determining whether the component already possesses the necessary decryption certificate. The information published by the other parameters in the event (i.e., Issuer, SerialNumber, and SubjectKeyIdentifier) may also be useful for determining which decryption certificate should be used.

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.

DecryptionCert Property (PDFDecrypt Component)

The decryption certificate.

Syntax

property DecryptionCert: TispCertificate read get_DecryptionCert write set_DecryptionCert;

Remarks

This property is used to provide the certificate used for decryption. Note that this certificate must have a private key associated with it.

This property is not available at design time.

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

InputData Property (PDFDecrypt Component)

A byte array containing the PDF document to process.

Syntax

property InputData: TBytes read get_InputData write set_InputData;

Remarks

This property is used to assign a byte array containing the PDF document to be processed.

This property is not available at design time.

InputFile Property (PDFDecrypt Component)

The PDF file to process.

Syntax

property InputFile: String read get_InputFile write set_InputFile;

Default Value

''

Remarks

This property is used to provide a path to the PDF document to be processed.

OutputData Property (PDFDecrypt Component)

A byte array containing the PDF document after processing.

Syntax

property OutputData: TBytes read get_OutputData;

Remarks

This property is used to read the byte array containing the produced output after the operation has completed. It will only be set if an output file and output stream have not been assigned via OutputFile and SetOutputStream respectively.

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

OutputFile Property (PDFDecrypt Component)

The path to a local file where the output will be written.

Syntax

property OutputFile: String read get_OutputFile write set_OutputFile;

Default Value

''

Remarks

This property is used to provide a path where the resulting PDF document will be saved after the operation has completed.

Overwrite Property (PDFDecrypt Component)

Whether or not the component should overwrite files.

Syntax

property Overwrite: Boolean read get_Overwrite write set_Overwrite;

Default Value

false

Remarks

This property indicates whether or not the component will overwrite OutputFile, OutputData, or the stream set in SetOutputStream. If set to False, an error will be thrown whenever OutputFile, OutputData, or the stream set in SetOutputStream exists before an operation.

Password Property (PDFDecrypt Component)

The password to decrypt the document with.

Syntax

property Password: String read get_Password write set_Password;

Default Value

''

Remarks

This property is used to provide the user password for decryption. Though it may be different from OwnerPassword, most implementations use the same value for both.

Close Method (PDFDecrypt Component)

Closes an opened PDF document.

Syntax

procedure Close();

Remarks

This method is used to close the previously opened document specified in InputFile, InputData, or SetInputStream. It should always be preceded by a call to the Open method.

Example: component.InputFile = "input.pdf"; component.Open(); // Some operation component.Close();

If any changes are made to the document, they will be saved automatically to OutputFile, OutputData, or the stream set in SetOutputStream when this method is called. To configure this saving behavior, set the SaveChanges configuration setting.

Config Method (PDFDecrypt 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.

Decrypt Method (PDFDecrypt Component)

Decrypts a PDF document.

Syntax

procedure Decrypt();

Remarks

This method is used to permanently remove encryption from the PDF document specified in InputFile, InputData, or SetInputStream. The document will be decrypted with either Password (for password-based encryption) or DecryptionCert (for certificate-based encryption) and saved in OutputFile, OutputData, or the stream set in SetOutputStream.

Example: pdfdecrypt.InputFile = "encrypted.pdf"; pdfdecrypt.OutputFile = "decrypted.pdf"; // Set decryption material (Password or DecryptionCert) here pdfdecrypt.Decrypt(); Note: Since full decryption invalidates all signatures, this method will automatically remove them from the document. Existing signatures should therefore be verified before calling this method.

Note: If the document is not already opened, this method will open it, perform the operation, then close it.

Encrypted Method (PDFDecrypt Component)

Checks whether a PDF document is encrypted.

Syntax

function Encrypted(): Boolean;

Remarks

This method is used to determine whether or not the document specified in InputFile, InputData, or SetInputStream is encrypted. It will return False if the document is pseudo-encrypted with an empty password.

Example: pdfdecrypt.InputFile = "input.pdf"; if (pdfdecrypt.Encrypted()) { pdfdecrypt.OutputFile = "decrypted.pdf"; // Set Password or DecryptionCert pdfdecrypt.Decrypt(); } Note: If the document is not already opened, this method will open it, perform the operation, then close it.

Open Method (PDFDecrypt Component)

Opens a PDF document for processing.

Syntax

procedure Open();

Remarks

This method is used to open the document specified in InputFile, InputData, or SetInputStream before performing some operation on it, such as decryption. When finished, call Close to complete or discard the operation.

It is recommended to use this method (alongside Close) when performing multiple operations on the document at once.

Automatic Decryption Functionality

If this method is called on an encrypted document, the Password or RecipientInfo event will fire (depending on the encryption type) as a notification that the document must be decrypted before processing can continue.

Once the correct decryption material is supplied, the component will then attempt to decrypt the document automatically within this method. When this occurs, the decrypted content is kept in memory so that the document's encrypted status is preserved when it is saved later. Use the Decrypt method to save a decrypted copy of the document instead.

Reset Method (PDFDecrypt Component)

Resets the component.

Syntax

procedure Reset();

Remarks

This method is used to reset the component's properties and configuration settings to their default values.

SetInputStream Method (PDFDecrypt Component)

Sets the stream containing the PDF document to process.

Syntax

procedure SetInputStream(InputStream: TStream);

Remarks

This method is used to set the stream from which the component will read the PDF document to be processed. If an input stream is set before the component attempts to perform operations on the document, the component will read the data from the input stream instead of from the InputFile or InputData properties.

Note: It may be useful to additionally set the CloseInputStreamAfterProcessing configuration setting to True when using input streams.

SetOutputStream Method (PDFDecrypt Component)

Sets the stream to write the processed document to.

Syntax

procedure SetOutputStream(OutputStream: TStream);

Remarks

This method is used to set the stream to which the component will write the resulting PDF document. If an output stream is set before the component attempts to perform operations on the document, the component will write the data to the output stream instead of writing to OutputFile or populating OutputData.

Note: It may be useful to additionally set the CloseOutputStreamAfterProcessing configuration setting to True when using output streams.

Error Event (PDFDecrypt Component)

Fired when information is available about errors during data delivery.

Syntax

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

property OnError: TErrorEvent read FOnError write FOnError;

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the component raises an exception.

The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

Log Event (PDFDecrypt Component)

Fired once for each log message.

Syntax

type TLogEvent = procedure (
  Sender: TObject;
  LogLevel: Integer;
  const Message: String;
  const LogType: String
) of Object;

property OnLog: TLogEvent read FOnLog write FOnLog;

Remarks

This event is fired once for each log message generated by the component. The verbosity is controlled by the LogLevel configuration setting.

The LogLevel parameter indicates the detail level of the message. Possible values are:

The Message parameter is the log message.

The LogType parameter identifies the type of log entry. Possible values are:

• CertValidator
• Font
• HTTP
• PDFInvalidSignature
• PDFRevocationInfo
• Timestamp
• TSL

Password Event (PDFDecrypt Component)

Fired when the component detects that the PDF document is encrypted with a password.

Syntax

type TPasswordEvent = procedure (
  Sender: TObject;
  Available: Boolean;
  var Cancel: Boolean
) of Object;

property OnPassword: TPasswordEvent read FOnPassword write FOnPassword;

Remarks

This event is fired during document processing to report that the document is encrypted with a password. It may be used to supply the correct decryption password to the Password property.

The Available parameter indicates whether the decryption password is already available to the component or still needs to be set. If this parameter is set to False, the correct password must be provided for the decryption attempt to succeed.

The Cancel parameter determines whether the component will stop firing this event to request a password.

RecipientInfo Event (PDFDecrypt Component)

Fired for each recipient certificate of the encrypted PDF document.

Syntax

type TRecipientInfoEvent = procedure (
  Sender: TObject;
  const Issuer: String;
  const SerialNumber: String;
  const SubjectKeyIdentifier: String;
  Available: Boolean;
  var Cancel: Boolean
) of Object;

property OnRecipientInfo: TRecipientInfoEvent read FOnRecipientInfo write FOnRecipientInfo;

Remarks

This event is fired during document processing for each recipient certificate that the document has been encrypted for (if applicable). It may be used to identify the certificate(s) to load and supply to the DecryptionCert property.

The Issuer parameter specifies the subject of the issuer certificate.

The SerialNumber parameter specifies the serial number of the encryption certificate.

The SubjectKeyIdentifier parameter specifies the X.509 subjectKeyIdentifier extension value of the encryption certificate, encoded as a hex string.

The Available parameter indicates whether the decryption certificate is already available to the component or still needs to be set. If this parameter is set to False, the correct certificate must be provided for the decryption attempt to succeed.

The Cancel parameter determines whether the component will stop firing this event to request a certificate.

Note: The document may be encrypted with more than one certificate (or have "more than one recipient"), in which case each certificate will cause its own invocation of this event.

Certificate Type

This is the digital certificate being used.

Remarks

This type describes the current digital certificate. The certificate may be a public or private key. The fields are used to identify or select certificates.

Fields

Constructors

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constructor Create();

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constructor Create(valEncoded: TBytes);

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constructor Create(valStoreType: TispCertStoreTypes; valStore: String; valStorePassword: String; valSubject: String);

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constructor Create(valStoreType: TispCertStoreTypes; valStore: TBytes; valStorePassword: String; valSubject: String);

Config Settings (PDFDecrypt 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.

PDFDecrypt Config Settings

Base Config Settings

Trappable Errors (PDFDecrypt Component)

PDFDecrypt Errors

PDF Errors

Parsing Errors