Log VB.NET WinRT Reference Documentation

Log

Handy logging class exposing much of the functionality used internally by Chilkat for LastErrorText, LastErrorXml, and LastErrorHtml.

Object Creation

Dim obj As New Chilkat.Log()

Properties

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.

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.

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.

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.

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.

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.

Version As String (ReadOnly)

Version of the component/library, such as "9.4.1.42"

Methods

Sub Clear(ByVal initialTag As String)

Introduced in version 9.5.0.44

Clears the log. The initialTag is the initial top-level context tag for the new log.

Sub EnterContext(ByVal tag As String)

Introduced in version 9.5.0.44

Enters a new context labelled with the given tag. Must be paired with a matching call to LeaveContext.

Sub LeaveContext()

Introduced in version 9.5.0.44

Leaves the current context. A context that is entered and exited without any logging within the context is automatically removed from the log. (To say it another way: Empty contexts are automaticallly removed from the log upon leaving the context.)

Sub LogData(ByVal tag As String, ByVal message As String)

Introduced in version 9.5.0.44

Adds a tagged message to the log (i.e. a name/value pair).

Sub LogDataBase64(ByVal tag As String, ByVal data As Byte())

Introduced in version 9.5.0.44

Logs binary data in base64 format.

Sub LogDataHex(ByVal tag As String, ByVal data As Byte())

Introduced in version 9.5.0.44

Logs binary data in hex format.

Sub LogDataMax(ByVal tag As String, ByVal message As String, ByVal maxNumChars As Integer)

Introduced in version 9.5.0.44

Logs a string, but only up to the 1st maxNumChars characters of the string.

Sub LogDateTime(ByVal tag As String, ByVal gmt As Boolean)

Introduced in version 9.5.0.44

Logs the current date/time in RFC822 format. If gmt is True, then the GMT/UTC time is logged. Otherwise it is the local time.

Sub LogError(ByVal message As String)

Introduced in version 9.5.0.44

Logs an error within the current context.

Sub LogInfo(ByVal message As String)

Introduced in version 9.5.0.44

Logs an informational message within the current context.

Sub LogInt(ByVal tag As String, ByVal value As Integer)

Introduced in version 9.5.0.44

Logs an integer.

Sub LogInt64(ByVal tag As String, ByVal value As Int64)

Introduced in version 9.5.0.44

Logs a 64-bit integer.

Sub LogTimestamp(ByVal tag As String)

Introduced in version 9.5.0.44

Logs the current time in HH:MM:SS:mmm format.

Function SaveLastError(ByVal path As String) As Boolean

Saves the last-error information (the contents of LastErrorXml) to an XML formatted file.

Returns True for success, False for failure.