Rss ActiveX Reference Documentation

Rss

Represents an RSS document or sub-part of a document such as a channel, image, or item. The RSS API allows one to download, create and modify RSS documents.

Object Creation

(Visual Basic 6.0)
Dim obj As New ChilkatRss

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

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

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

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

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

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

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

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.

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.

NumChannels As Long (read-only)

The number of channels in the RSS document.

NumItems As Long (read-only)

The number of items in the channel.

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

AddNewChannel() As ChilkatRss

Adds a new channel to the RSS document. Returns the Rss object representing the Channel which can then be edited.

Returns Nothing on failure

AddNewImage() As ChilkatRss

Adds a new image to the RSS document. Returns the Rss object representing the image, which can then be edited.

Returns Nothing on failure

AddNewItem() As ChilkatRss

Adds a new Item to an Rss channel. Returns the Rss object representing the item which can then be edited.

Returns Nothing on failure

DownloadRss(url As String) As Long

Downloads an RSS document from the Internet and populates the Rss object with the contents.

Returns 1 for success, 0 for failure.

(Classic ASP) Example: Read RSS Feed

(Visual FoxPro) Example: Read RSS Feed

(PowerBuilder) Example: Read RSS Feed

(SQL Server) Example: Read RSS Feed

(Visual Basic 6.0) Example: Read RSS Feed

(VBScript) Example: Read RSS Feed

DownloadRssAsync(url As String) As ChilkatTask

Creates an asynchronous task to call the DownloadRss 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

GetAttr(tag As String, attrName As String) As String

Returns the value of a sub-element attribute. For example, to get the value of the "isPermaLink" attribute of the "guid" sub-element, call item.GetAttr("guid","isPermaLink").

Returns Nothing on failure

GetChannel(ByVal index As Long) As ChilkatRss

Returns the Nth channel of an RSS document. Usually there is only 1 channel per document, so the index argument should be set to 0.

Returns Nothing on failure

GetCount(tag As String) As Long

Return the number of sub-elements with a specific tag.

GetDate(tag As String) As Date

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

Return the value of a sub-element in date/time format.

GetDateStr(tag As String) As String

The same as GetDate, except the date/time is returned in RFC822 string format.

Returns Nothing on failure

GetImage() As ChilkatRss

Return the image associated with the channel.

Returns Nothing on failure

GetInt(tag As String) As Long

Return the value of a numeric sub-element as an integer.

GetItem(ByVal index As Long) As ChilkatRss

Return the Nth item of a channel as an RSS object.

Returns Nothing on failure

GetString(tag As String) As String

Return the value of an sub-element as a string.

Returns Nothing on failure

LoadRssFile(filePath As String) As Long

Load an RSS document from a file.

Returns 1 for success, 0 for failure.

LoadRssString(rssString As String) As Long

Loads an RSS feed document from an in-memory string.

Returns 1 for success, 0 for failure.

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

Get an attribute value for the Nth sub-element having a specific tag. As an example, an RSS item may have several "category" sub-elements. To get the value of the "domain" attribute for the 3rd category, call MGetAttr("category",2,"domain").

Returns Nothing on failure

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

Get the value of the Nth occurrence of a sub-element. Indexing begins at 0.

Returns Nothing on failure

MSetAttr(tag As String, ByVal idx As Long, attrName As String, value As String) As Long

Set an attribute on the Nth occurrence of a sub-element.

Returns 1 for success, 0 for failure.

MSetString(tag As String, ByVal idx As Long, value As String) As Long

Set the value of the Nth occurrence of a sub-element. Indexing begins at 0.

Returns 1 for success, 0 for failure.

NewRss()

Clears the RSS document.

Remove(tag As String)

Removes a sub-element from the RSS document.

SetAttr(tag As String, attrName As String, value As String)

Sets the value of a sub-element attribute.

SetDate(tag As String, ByVal dateTime As Date)

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

Sets the value of a date/time sub-element.

SetDateNow(tag As String)

Sets the value of a date/time sub-element to the current system date/time.

SetDateStr(tag As String, dateTimeStr As String)

The same as SetDate, except the date/time is passed as an RFC822 string.

SetInt(tag As String, ByVal value As Long)

Sets the value of an integer sub-element.

SetString(tag As String, value As String)

Sets the value of a sub-element.

ToXmlString() As String

Returns the RSS document as an XML string.

Returns Nothing on failure

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 myRss As ChilkatRss

Private Sub myRss_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 myRss As ChilkatRss

Private Sub myRss_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 myRss As ChilkatRss

Private Sub myRss_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 myRss As ChilkatRss

Private Sub myRss_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 myRss As ChilkatRss

Private Sub myRss_TextData(data As String)

	'Insert application code here.

End Sub