Rss VB.NET WinRT Reference Documentation

Rss

Current Version: 9.5.0.90

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

Dim obj As New Chilkat.Rss()

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:

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

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.

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.

More Information and Examples

Concept of LastErrorText LastErrorText Standard Information

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.

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.

NumChannels

NumChannels As Integer (ReadOnly)

The number of channels in the RSS document.

NumItems

NumItems As Integer (ReadOnly)

The number of items in the channel.

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.

Version

Version As String (ReadOnly)

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

Methods

AddNewChannel

Function AddNewChannel() As Rss

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

Function AddNewImage() As Rss

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

Function AddNewItem() As Rss

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

<Awaitable> Function DownloadRssAsyncAsync(ByVal url As String) As IAsyncOperation(Of Boolean)

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

Returns True for success, False for failure.

More Information and Examples

Example: Read RSS Feed

GetAttr

Function GetAttr(ByVal tag As String, ByVal 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

Function GetChannel(ByVal index As Integer) As Rss

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

Function GetCount(ByVal tag As String) As Integer

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

GetDateStr

Function GetDateStr(ByVal tag As String) As String

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

Returns Nothing on failure

GetImage

Function GetImage() As Rss

Return the image associated with the channel.

Returns Nothing on failure

GetInt

Function GetInt(ByVal tag As String) As Integer

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

GetItem

Function GetItem(ByVal index As Integer) As Rss

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

Returns Nothing on failure

GetString

Function GetString(ByVal tag As String) As String

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

Returns Nothing on failure

LoadRssFile

Function LoadRssFile(ByVal filePath As String) As Boolean

Load an RSS document from a file.

Returns True for success, False for failure.

LoadRssString

Function LoadRssString(ByVal rssString As String) As Boolean

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

Returns True for success, False for failure.

MGetAttr

Function MGetAttr(ByVal tag As String, ByVal index As Integer, ByVal 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

Function MGetString(ByVal tag As String, ByVal index As Integer) As String

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

Returns Nothing on failure

MSetAttr

Function MSetAttr(ByVal tag As String, ByVal idx As Integer, ByVal attrName As String, ByVal value As String) As Boolean

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

Returns True for success, False for failure.

MSetString

Function MSetString(ByVal tag As String, ByVal idx As Integer, ByVal value As String) As Boolean

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

Returns True for success, False for failure.

NewRss

Sub NewRss()

Clears the RSS document.

Remove

Sub Remove(ByVal tag As String)

Removes a sub-element from the RSS document.

SetAttr

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

Sets the value of a sub-element attribute.

SetDateNow

Sub SetDateNow(ByVal tag As String)

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

SetDateStr

Sub SetDateStr(ByVal tag As String, ByVal dateTimeStr As String)

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

SetInt

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

Sets the value of an integer sub-element.

SetString

Sub SetString(ByVal tag As String, ByVal value As String)

Sets the value of a sub-element.

ToXmlString

Function ToXmlString() As String

Returns the RSS document as an XML string.

Returns Nothing on failure

Events