Rss C# 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

Chilkat.Rss obj = new Chilkat.Rss();

Properties

DebugLogFilePath

public string DebugLogFilePath {get; set; }

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

public string LastErrorHtml {get; }

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

public string LastErrorText {get; }

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

public string LastErrorXml {get; }

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

public bool LastMethodSuccess {get; set; }

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

public int NumChannels {get; }

The number of channels in the RSS document.

NumItems

public int NumItems {get; }

The number of items in the channel.

VerboseLogging

public bool VerboseLogging {get; set; }

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

public string Version {get; }

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

Methods

AddNewChannel

public Rss AddNewChannel();

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

Returns null on failure

AddNewImage

public Rss AddNewImage();

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

Returns null on failure

AddNewItem

public Rss AddNewItem();

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

Returns null on failure

DownloadRss

(awaitable) public IAsyncOperation<bool> DownloadRssAsyncAsync(string url);

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

public string GetAttr(string tag, string attrName);

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 null on failure

GetChannel

public Rss GetChannel(int index);

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 null on failure

GetCount

public int GetCount(string tag);

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

GetDateStr

public string GetDateStr(string tag);

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

Returns null on failure

GetImage

public Rss GetImage();

Return the image associated with the channel.

Returns null on failure

GetInt

public int GetInt(string tag);

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

GetItem

public Rss GetItem(int index);

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

Returns null on failure

GetString

public string GetString(string tag);

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

Returns null on failure

LoadRssFile

public bool LoadRssFile(string filePath);

Load an RSS document from a file.

Returns true for success, false for failure.

LoadRssString

public bool LoadRssString(string rssString);

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

Returns true for success, false for failure.

MGetAttr

public string MGetAttr(string tag, int index, string attrName);

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 null on failure

MGetString

public string MGetString(string tag, int index);

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

Returns null on failure

MSetAttr

public bool MSetAttr(string tag, int idx, string attrName, string value);

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

Returns true for success, false for failure.

MSetString

public bool MSetString(string tag, int idx, string value);

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

Returns true for success, false for failure.

NewRss

public void NewRss();

Clears the RSS document.

Remove

public void Remove(string tag);

Removes a sub-element from the RSS document.

SetAttr

public void SetAttr(string tag, string attrName, string value);

Sets the value of a sub-element attribute.

SetDateNow

public void SetDateNow(string tag);

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

SetDateStr

public void SetDateStr(string tag, string dateTimeStr);

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

SetInt

public void SetInt(string tag, int value);

Sets the value of an integer sub-element.

SetString

public void SetString(string tag, string value);

Sets the value of a sub-element.

ToXmlString

public string ToXmlString();

Returns the RSS document as an XML string.

Returns null on failure

Events

Callbacks from asynchronous methods occur in a background thread. However, controls on the UI thread may only be accessed from the UI thread.Therefore, UI updates must be dispatched to the UI thread. One way to do this is as follows:

    public sealed partial class MainPage : Page
    {
        private Windows.UI.Core.CoreDispatcher m_dispatcher = null;

        public MainPage()
        {
            this.InitializeComponent();
            m_dispatcher = Windows.UI.Core.CoreWindow.GetForCurrentThread().Dispatcher;
        }


        async private void Http_ProgressInfo(object sender, Chilkat.ProgressInfoEventArgs eventArgs)
        {
            await m_dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
            {
                // Application code to update the UI goes here...
            });
        }

    }