Atom ActiveX Reference Documentation

Atom

Represents an Atom document. The Atom API allows one to download, create and modify Atom documents.

Object Creation

(Visual Basic 6.0)
Dim obj As New ChilkatAtom

(ASP)
set obj = Server.CreateObject("Chilkat_9_5_0.Atom")

(VBScript)
set obj = CreateObject("Chilkat_9_5_0.Atom")

(Delphi)
obj := TChilkatAtom.Create(Self);

(FoxPro)
loObject = CreateObject('Chilkat_9_5_0.Atom')

(PowerBuilder)
lole_object = create oleobject
li_rc = lole_object.ConnectToNewObject("Chilkat_9_5_0.Atom")

(SQL Server)
EXEC @hr = sp_OACreate 'Chilkat_9_5_0.Atom', @obj OUT

(Javascript)
var obj = new ActiveXObject("Chilkat_9_5_0.Atom");

Properties

AbortCurrent As Long (read-only)

Introduced in version 9.5.0.58

When set to 1, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to 0 when the next method is called. When the abort occurs, this property is reset to 0. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)

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.

LastBinaryResult As Variant (read-only)

Introduced in version 9.5.0.52

The binary data returned by the last (binary data returning) method called. Only available if Chilkat.Global.KeepBinaryResult is set to 1. This provides a means for obtaining large varbinary results in the SQL Server environment (where limitations exist in getting large amounts of data returned by method calls, but where temp tables can be used for binary properties).

LastErrorHtml As String (read-only)

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 (read-only)

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.

Concept of LastErrorText

LastErrorText Standard Information

LastErrorXml As String (read-only)

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 Long

Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of 1 indicates success, a value of 0 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 = 1 and failure = 0.
  • 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 1. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

LastStringResult As String (read-only)

Introduced in version 9.5.0.52

The string return value of the last (string returning) method called. Only available if Chilkat.Global.KeepStringResult is set to 1. This provides a means for obtaining large string results in the SQL Server environment (where limitations exist in getting long strings returned by method calls, but where temp tables can be used for string properties).

Long Strings Returned by ActiveX Methods in SQL Server

LastStringResultLen As Long (read-only)

Introduced in version 9.5.0.53

The length, in characters, of the string contained in the LastStringResult property.

NumEntries As Long (read-only)

Number of entries in the Atom document.

VerboseLogging As Long

If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

Version As String (read-only)

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

Methods

AddElement(tag As String, value As String) As Long

Adds a new element to the Atom document. The tag is a string such as "title", "subtitle", "summary", etc. Returns the index of the element added, or -1 for failure.

AddElementDate(tag As String, ByVal dateTime As Date) As Long

This method is deprecated. It will be removed in a future version.

Adds a new date-formatted element to the Atom document. The tag is a string such as "created", "modified", "issued", etc. Returns the index of the element added, or -1 for failure.

AddElementDateStr(tag As String, dateTimeStr As String) As Long

Adds a new date-formatted element to the Atom document. The tag is a string such as "created", "modified", "issued", etc. The dateTimeStr should be an RFC822 formatted date/time string such as "Tue, 25 Sep 2012 12:25:32 -0500". Returns the index of the element added, or -1 for failure.

AddElementDt(tag As String, dateTime As CkDateTime) As Long

Adds a new date-formatted element to the Atom document. The tag is a string such as "created", "modified", "issued", etc. Returns the index of the element added, or -1 for failure.

AddElementHtml(tag As String, htmlStr As String) As Long

Adds a new HTML formatted element to the Atom document. Returns the index of the element added, or -1 for failure.

AddElementXHtml(tag As String, xmlStr As String) As Long

Adds a new XHTML formatted element to the Atom document. Returns the index of the element added, or -1 for failure.

AddElementXml(tag As String, xmlStr As String) As Long

Adds a new XML formatted element to the Atom document. Returns the index of the element added, or -1 for failure.

AddEntry(xmlStr As String)

Adds an "entry" Atom XML document to the caller's Atom document.

AddLink(rel As String, href As String, title As String, typ As String)

Adds a link to the Atom document.

AddPerson(tag As String, name As String, uri As String, email As String)

Adds a person to the Atom document. The tag should be a string such as "author", "contributor", etc. If a piece of information is not known, an empty string or NULL value may be passed.

DeleteElement(tag As String, ByVal index As Long)

Removes the Nth occurrence of a given element from the Atom document. Indexing begins at 0. For example, to remove the 2nd category, set tag = "category" and index = 1.

DeleteElementAttr(tag As String, ByVal index As Long, attrName As String)

Remove an attribute from an element.The index should be 0 unless there are multiple elements having the same tag, in which case it selects the Nth occurrence based on the index ( 0 = first occurrence ).

DeletePerson(tag As String, ByVal index As Long)

Deletes a person from the Atom document. The tag is a string such as "author". The index should be 0 unless there are multiple elements having the same tag, in which case it selects the Nth occurrence based on the index. For example, DeletePerson("author",2) deletes the 3rd author.

DownloadAtom(url As String) As Long

Download an Atom feed from the Internet and load it into the Atom object.

Returns 1 for success, 0 for failure.

DownloadAtomAsync(url As String) As ChilkatTask

Creates an asynchronous task to call the DownloadAtom 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

(Classic ASP) How to Run an Asynchronous Task

(Visual FoxPro) How to Run an Asynchronous Task

(PowerBuilder) How to Run an Asynchronous Task

(SQL Server) How to Run an Asynchronous Task

(Visual Basic 6.0) How to Run an Asynchronous Task

(VBScript) How to Run an Asynchronous Task

Asynchronous Methods in VB6 - Be Very Careful with Callbacks

GetElement(tag As String, ByVal index As Long) As String

Returns the content of the Nth element having a specified tag.

Returns Nothing on failure

GetElementAttr(tag As String, ByVal index As Long, attrName As String) As String

Returns the value of an element's attribute. The element is selected by the tag name and the index (the Nth element having a specific tag) and the attribute is selected by name.

Returns Nothing on failure

GetElementCount(tag As String) As Long

The number of elements having a specific tag.

GetElementDate(tag As String, ByVal index As Long) As Date

This method is deprecated. It will be removed in a future version.

Returns an element's value as a date/time.

GetElementDateStr(tag As String, ByVal index As Long) As String

Returns an element's value as a date/time in an RFC822 formatted string, such as such as "Tue, 25 Sep 2012 12:25:32 -0500".

Returns Nothing on failure

GetElementDt(tag As String, ByVal index As Long) As CkDateTime

Returns an element's value as a date/time object.

Returns Nothing on failure

GetEntry(ByVal index As Long) As ChilkatAtom

Returns the Nth entry as an Atom object. (Indexing begins at 0)

Returns Nothing on failure

GetLinkHref(relName As String) As String

Returns the href attribute of the link having a specified "rel" attribute (such as "service.feed", "alternate", etc.).

Returns Nothing on failure

GetPersonInfo(tag As String, ByVal index As Long, tag2 As String) As String

Returns a piece of information about a person. To get the 2nd author's name, call GetPersonInfo("author",1,"name").

Returns Nothing on failure

GetTopAttr(attrName As String) As String

Returns the value of an attribute on the top-level XML node. The tag of a top-level Atom XML node is typically "feed" or "entry", and it might have attributes such as "xmlns" and "xml:lang".

Returns Nothing on failure

HasElement(tag As String) As Long

True (1) if the element exists in the Atom document. Otherwise 0.

LoadXml(xmlStr As String) As Long

Loads the Atom document from an XML string.

Returns 1 for success, 0 for failure.

NewEntry()

Initializes the Atom document to be a new "entry".

NewFeed()

Initializes the Atom document to be a new "feed".

SetElementAttr(tag As String, ByVal index As Long, attrName As String, attrValue As String)

Adds or replaces an attribute on an element.

SetTopAttr(attrName As String, value As String)

Adds or replaces an attribute on the top-level XML node of the Atom document.

ToXmlString() As String

Serializes the Atom document to an XML string.

Returns Nothing on failure

UpdateElement(tag As String, ByVal index As Long, value As String)

Replaces the content of an element.

UpdateElementDate(tag As String, ByVal index As Long, ByVal dateTime As Date)

This method is deprecated. It will be removed in a future version.

Replaces the content of a date-formatted element.

UpdateElementDateStr(tag As String, ByVal index As Long, dateTimeStr As String)

Replaces the content of a date-formatted element. The index should be an RFC822 formatted date/time string.

UpdateElementDt(tag As String, ByVal index As Long, dateTime As CkDateTime)

Replaces the content of a date-formatted element.

UpdateElementHtml(tag As String, ByVal index As Long, htmlStr As String)

Replaces the content of an HTML element.

UpdateElementXHtml(tag As String, ByVal index As Long, xmlStr As String)

Replaces the content of an XHTML element.

UpdateElementXml(tag As String, ByVal index As Long, xmlStr As String)

Replaces the content of an XML element.

UpdatePerson(tag As String, ByVal index As Long, name As String, uri As String, email As String)

Replaces the content of a person. To update the 3rd author, call UpdatePerson("author",2,"new name","new URL","new email"). If a piece of information is not known, pass an empty string or a NULL.

Events

AbortCheck(abort As Long)

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.

VB6 Event callback implementation:

Important: Event callbacks from asynchronous method calls are generally not possible from the ActiveX. See VB6 Async Callbacks

Dim WithEvents myAtom As ChilkatAtom

Private Sub myAtom_AbortCheck(abort As Long)

	'Insert application code here.

End Sub

BinaryData(data As Variant)

Binary data provided by certain methods.

VB6 Event callback implementation:

Important: Event callbacks from asynchronous method calls are generally not possible from the ActiveX. See VB6 Async Callbacks

Dim WithEvents myAtom As ChilkatAtom

Private Sub myAtom_BinaryData(data As Variant)

	'Insert application code here.

End Sub

PercentDone(ByVal pctDone As Long, abort As Long)

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 1 will cause the method to abort and return a failed status (or whatever return value indicates failure).

VB6 Event callback implementation:

Important: Event callbacks from asynchronous method calls are generally not possible from the ActiveX. See VB6 Async Callbacks

Dim WithEvents myAtom As ChilkatAtom

Private Sub myAtom_PercentDone(ByVal pctDone As Long, abort As Long)

	'Insert application code here.

End Sub

ProgressInfo(name As String, value As String)

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.

VB6 Event callback implementation:

Important: Event callbacks from asynchronous method calls are generally not possible from the ActiveX. See VB6 Async Callbacks

Dim WithEvents myAtom As ChilkatAtom

Private Sub myAtom_ProgressInfo(name As String, value As String)

	'Insert application code here.

End Sub

TextData(data As String)

Text data provided by certain methods.

VB6 Event callback implementation:

Important: Event callbacks from asynchronous method calls are generally not possible from the ActiveX. See VB6 Async Callbacks

Dim WithEvents myAtom As ChilkatAtom

Private Sub myAtom_TextData(data As String)

	'Insert application code here.

End Sub