Pdf VB.NET Reference Documentation

Pdf

Current Version: 9.5.0.88

A PDF class for various tasks such as signature verification, signing, encrypt, decrypt, etc.

Object Creation

Dim obj As New Chilkat.Pdf()

Properties

DebugLogFilePath
DebugLogFilePath As String

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

  1. a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
  2. the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
  3. there is an internal problem (bug) in the Chilkat code that causes the hang.

top
LastErrorHtml
LastErrorHtml As String (ReadOnly)

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

top
LastErrorText
LastErrorText As String (ReadOnly)

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

top
LastErrorXml
LastErrorXml As String (ReadOnly)

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

top
LastMethodSuccess
LastMethodSuccess As Boolean
Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of True indicates success, a value of False indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

  • Any method that returns a string.
  • Any method returning a Chilkat object, binary bytes, or a date/time.
  • Any method returning a standard boolean status value where success = True and failure = False.
  • Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to True. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

top
NumPages
NumPages As Integer (ReadOnly)
Introduced in version 9.5.0.85

The number of pages in the currently open PDF.

top
NumSignatures
NumSignatures As Integer (ReadOnly)
Introduced in version 9.5.0.85

The number of digital signatures present in the currently open PDF.

top
UncommonOptions
UncommonOptions As String
Introduced in version 9.5.0.85

This is a catch-all property to be used for uncommon needs. This property defaults to the empty string. Can be set to a list of the following comma separated keywords:

  • "WriteStandardXref" - When writing the PDF, write the cross reference section in standard format if possible. (The "standard format" is the older non-compressed format.)

top
VerboseLogging
VerboseLogging As Boolean

If set to True, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is False. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

top
Version
Version As String (ReadOnly)

Version of the component/library, such as "9.5.0.63"

top

Methods

AddSigningCert
Function AddSigningCert(ByVal cert As Cert) As Boolean
Introduced in version 9.5.0.85

Adds a certificate to be used for PDF signing. To sign with more than one certificate, call AddSigningCert once per certificate.

Note: This method is used to provide the ability to sign once with multiple certificates. This is different than signing with one certificate, and then signing again with a different certificate.

Returns True for success, False for failure.

top
GetDss
Function GetDss(ByVal json As JsonObject) As Boolean
Introduced in version 9.5.0.85

Gets the contents of the PDF's Document Security Store (/DSS) if it exists. Returns the information in JSON format (in json). If there is no /DSS then an empty JSON document "{}" is returned in json.

Returns True for success, False for failure.

More Information and Examples
top
GetSignerCert
Function GetSignerCert(ByVal index As Integer, ByVal cert As Cert) As Boolean
Introduced in version 9.5.0.87

This method can be used to get the signer certificate after calling VerifySignature. The index should be the same value as the index passed to VerifySignature. If successful, and if the signer certificate is fully available within the signature, the cert is loaded with the signer certificate.

Returns True for success, False for failure.

More Information and Examples
top
LastJsonData
Function LastJsonData() As JsonObject
Introduced in version 9.5.0.88

Provides information about what transpired in the last method called. For many methods, there is no information. For some methods, details about what transpired can be obtained via LastJsonData. For example, after calling a method to verify a signature, the LastJsonData will return JSON with details about the algorithms used for signature verification.

Returns Nothing on failure

top
LoadBd
Function LoadBd(ByVal pdfData As BinData) As Boolean
Introduced in version 9.5.0.85

Loads the PDF file contained in pdfData.

Returns True for success, False for failure.

top
LoadFile
Function LoadFile(ByVal filePath As String) As Boolean
Introduced in version 9.5.0.85

Load a PDF file into this object in memory.

Returns True for success, False for failure.

top
SetHttpObj
Sub SetHttpObj(ByVal http As Http)
Introduced in version 9.5.0.85

Sets the HTTP object to be used to communicate with the timestamp authority (TSA) server for cases where long term validation (LTV) of signatures is desired. The http is used to send the requests, and it allows for connection related settings and timeouts to be set. For example, if HTTP or SOCKS proxies are required, these features can be specified on the http.

The http is also used to send OCSP requests to store OCSP responses in the PDF's document security store (DSS).

Returns True for success, False for failure.

More Information and Examples
top
SetSignatureJpeg
Function SetSignatureJpeg(ByVal jpgData As BinData) As Boolean
Introduced in version 9.5.0.85

Provides an optional JPG image to be included in the signature appearance. The JPG data is passed in jpgData.

Returns True for success, False for failure.

top
SetSigningCert
Function SetSigningCert(ByVal cert As Cert) As Boolean
Introduced in version 9.5.0.85

Specifies a certificate to be used when signing the PDF. Signing requires both a certificate and private key. In this case, the private key is implicitly specified if the certificate originated from a PFX that contains the corresponding private key, or if on a Windows-based computer where the certificate and corresponding private key are pre-installed.

Returns True for success, False for failure.

top
SetSigningCert2
Function SetSigningCert2(ByVal cert As Cert, ByVal privateKey As PrivateKey) As Boolean
Introduced in version 9.5.0.85

Specifies a digital certificate and private key to be used for signing the PDF.

Returns True for success, False for failure.

top
SignPdf
Function SignPdf(ByVal jsonOptions As JsonObject, ByVal outFilePath As String) As Boolean
Introduced in version 9.5.0.85

Signs the open PDF and if successful writes the signed PDF to the ARG3. The jsonOptions contains information and instructions about the signature.

Returns True for success, False for failure.

More Information and Examples
top
SignPdfAsync (1)
Function SignPdfAsync(ByVal jsonOptions As JsonObject, ByVal outFilePath As String) As Task
Introduced in version 9.5.0.85

Creates an asynchronous task to call the SignPdf method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns Nothing on failure

top
VerifySignature
Function VerifySignature(ByVal index As Integer, ByVal sigInfo As JsonObject) As Boolean
Introduced in version 9.5.0.85

Verifies the Nth signature contained in the PDF, where the 1st signature is indicated by an index of 0. Returns True if the signature valid, otherwise returns False. The sigInfo is an output argument and is populated with information about the validated or unvalidated signature.

Returns True for success, False for failure.

More Information and Examples
top

Events

AbortCheck
Event OnAbortCheck

Provides the opportunity for a method call to be aborted. The AbortCheck event is fired periodically based on the value of the HeartbeatMs property. If HeartbeatMs is 0, then no AbortCheck events will fire. As an example, to fire 5 AbortCheck events per second, set the HeartbeatMs property equal to 200.

Args are passed using Chilkat.AbortCheckEventArgs

Event callback implementation:

Dim WithEvents pdf As Chilkat.Pdf

Private Sub pdf_OnAbortCheck(sender As Object, args As Chilkat.AbortCheckEventArgs) Handles pdf.OnAbortCheck

    ...

End Sub
top
PercentDone
Event OnPercentDone

Provides the percentage completed for any method that involves network communications or time-consuming processing (assuming it is a method where a percentage completion can be measured). This event is only fired when it is possible to know a percentage completion, and when it makes sense to express the operation as a percentage completed. The pctDone argument will have a value from 1 to 100. For operations (Chilkat method calls) that complete very quickly, the number of PercentDone callbacks will vary, but the final callback should have a value of 100. For long running operations, no more than one callback per percentage point will occur (for example: 1, 2, 3, ... 98, 99, 100).

The PercentDone callback counts as an AbortCheck event. For method calls that complete quickly such that PercentDone events fire, it may be that AbortCheck events don't fire because the opportunity to abort is already provided in the PercentDone callback. For time consuming operations, where the amount of time between PercentDone callbacks are long, AbortCheck callbacks may be used to allow for the operation to be aborted in a more responsive manner.

The abort output argument provides a means for aborting the operation. Setting it to True will cause the method to abort and return a failed status (or whatever return value indicates failure).

Args are passed using Chilkat.PercentDoneEventArgs

Event callback implementation:

Dim WithEvents pdf As Chilkat.Pdf

Private Sub pdf_OnPercentDone(sender As Object, args As Chilkat.PercentDoneEventArgs) Handles pdf.OnPercentDone

    ...

End Sub
top
ProgressInfo
Event OnProgressInfo

A general name/value event that provides information about what is happening during a method call. To find out what information is available, write code to handle this event and log the name/value pairs. Most are self-explanatory.

Args are passed using Chilkat.ProgressInfoEventArgs

Event callback implementation:

Dim WithEvents pdf As Chilkat.Pdf

Private Sub pdf_OnProgressInfo(sender As Object, args As Chilkat.ProgressInfoEventArgs) Handles pdf.OnProgressInfo

    ...

End Sub
top
TaskCompleted
Event OnTaskCompleted

Called in the background thread when an asynchronous task completes.

More Information and Examples

Args are passed using Chilkat.TaskCompletedEventArgs

Event callback implementation:

Dim WithEvents pdf As Chilkat.Pdf

Private Sub pdf_OnTaskCompleted(sender As Object, args As Chilkat.TaskCompletedEventArgs) Handles pdf.OnTaskCompleted

    ...

End Sub
top