ZipCrc

If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.

Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.

Possible causes of hangs include:

• A timeout property set to 0, indicating an infinite timeout.
• A hang occurring within an event callback in the application code.
• An internal bug in the Chilkat code causing the hang.

Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

Indicates the success or failure of the most recent method call: True means success, False means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.

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.

Version of the component/library, such as "10.1.0"

Provides a way to calculate a CRC by streaming the data a chunk at a time. An application would start by calling BeginStream. Then it would add data by calling MoreData for each additional chunk. After the last chunk has been processed, the EndStream method is called to return the CRC.

Calculates a 32-bit CRC for in-memory byte data. This is the 32-bit CRC that would be found in a Zip file header if a file containing the data was added to a zip archive. Returns the CRC32 of the data.

Calculates a CRC32 for the bytes contained in bd.

Calculates a CRC32 for the string contained in sb. The charset is the byte representation to be used for the sb when calculating the CRC32. It can be utf-8, utf-16, windows-1252, iso-8859-1, or any of the character encodings (charsets) listed at the link below.

Calculates a CRC32 for a string. The charset is the byte representation to be used for the str when calculating the CRC32. It can be utf-8, utf-16, windows-1252, iso-8859-1, or any of the character encodings (charsets) listed at the link below.

Finalizes and returns the Zip CRC value calculated by calling BeginStream followed by multiple calls to MoreData.

Calculates the CRC32 of a file. The data contained in the file is streamed for the calculation to keep the memory footprint small and constant. Returns the CRC32 of the file.

Creates an asynchronous task to call the FileCrc method with the arguments provided.

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

Loads the caller of the task's async method.

Returns True for success, False for failure.

Adds additional data to the CRC currently being calculated. (See BeginStream for more information.)

Converts a 32-bit integer to a hex string.

Returns Nothing on failure

Enables a method call to be aborted by triggering the AbortCheck event at intervals defined by the HeartbeatMs property. If HeartbeatMs is set to its default value of 0, no events will occur. For instance, set HeartbeatMs to 200 to trigger 5 AbortCheck events per second.

Args are passed using Chilkat.AbortCheckEventArgs

Event callback implementation:

Dim WithEvents zipcrc As Chilkat.ZipCrc

Private Sub zipcrc_OnAbortCheck(sender As Object, args As Chilkat.AbortCheckEventArgs) Handles zipcrc.OnAbortCheck

    ...

End Sub

This provides the percentage completion for any method involving network communications or time-consuming processing, assuming the progress can be measured as a percentage. This event is triggered only when it's possible and logical to express the operation's progress as a percentage. The pctDone argument will range from 1 to 100. For methods that finish quickly, the number of PercentDone callbacks may vary, but the final callback will have pctDone equal to 100. For longer operations, callbacks will not exceed one per percentage point (e.g., 1, 2, 3, ..., 98, 99, 100).

The PercentDone callback also acts as an AbortCheck event. For fast methods where PercentDone fires, an AbortCheck event may not trigger since the PercentDone callback already provides an opportunity to abort. For longer operations, where time between PercentDone callbacks is extended, AbortCheck callbacks enable more responsive operation termination.

To abort the operation, set the abort output argument to True. This will cause the method to terminate and return a failure status or corresponding failure value.

Args are passed using Chilkat.PercentDoneEventArgs

Event callback implementation:

Dim WithEvents zipcrc As Chilkat.ZipCrc

Private Sub zipcrc_OnPercentDone(sender As Object, args As Chilkat.PercentDoneEventArgs) Handles zipcrc.OnPercentDone

    ...

End Sub

This event callback provides tag name/value pairs that detail what occurs during a method call. To discover existing tag names, create code to handle the event, emit the pairs, and review them. Most tag names are self-explanatory.

Note: Some Chilkat methods don't fire any ProgressInfo events.

Args are passed using Chilkat.ProgressInfoEventArgs

Event callback implementation:

Dim WithEvents zipcrc As Chilkat.ZipCrc

Private Sub zipcrc_OnProgressInfo(sender As Object, args As Chilkat.ProgressInfoEventArgs) Handles zipcrc.OnProgressInfo

    ...

End Sub

Called from the background thread when an asynchronous task completes.

Args are passed using Chilkat.TaskCompletedEventArgs

Event callback implementation:

Dim WithEvents zipcrc As Chilkat.ZipCrc

Private Sub zipcrc_OnTaskCompleted(sender As Object, args As Chilkat.TaskCompletedEventArgs) Handles zipcrc.OnTaskCompleted

    ...

End Sub