Rss C# Reference Documentation
Rss
Current Version: 10.1.0
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
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
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.
topLastErrorText
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
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.
topLastMethodSuccess
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.
topNumChannels
The number of channels in the RSS document.
topNumItems
The number of items in the channel.
topVerboseLogging
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.
topVersion
Methods
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
topAddNewImage
Adds a new image to the RSS document. Returns the Rss object representing the image, which can then be edited.
Returns null on failure
topAddNewItem
Adds a new Item to an Rss channel. Returns the Rss object representing the item which can then be edited.
Returns null on failure
topDownloadRss
Downloads an RSS document from the Internet and populates the Rss object with the contents.
Returns true for success, false for failure.
DownloadRssAsync (.NET Core C#) (C#) (Mono C#) (PowerShell)
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 null on failure
topGetAttr
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
topGetChannel
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
topGetCount
Return the number of sub-elements with a specific tag.
topGetDateStr
The same as GetDate, except the date/time is returned in RFC822 string format.
Returns null on failure
topGetImage
GetInt
Return the value of a numeric sub-element as an integer.
topGetItem
GetString
LoadRssFile
LoadRssString
Loads an RSS feed document from an in-memory string.
Returns true for success, false for failure.
topLoadTaskCaller
MGetAttr
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
topMGetString
Get the value of the Nth occurrence of a sub-element. Indexing begins at 0.
Returns null on failure
topMSetAttr
Set an attribute on the Nth occurrence of a sub-element.
Returns true for success, false for failure.
topMSetString
Set the value of the Nth occurrence of a sub-element. Indexing begins at 0.
Returns true for success, false for failure.
topNewRss
Clears the RSS document.
topRemove
Removes a sub-element from the RSS document.
topSetAttr
Sets the value of a sub-element attribute.
topSetDateNow
Sets the value of a date/time sub-element to the current system date/time.
topSetDateStr
The same as SetDate, except the date/time is passed as an RFC822 string.
topSetInt
Sets the value of an integer sub-element.
topSetString
Sets the value of a sub-element.
topToXmlString
Events
AbortCheck
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.
Chilkat .NET Event Implementation
Args are passed using Chilkat.AbortCheckEventArgs
Event callback implementation:
private void rss_OnAbortCheck(object sender, Chilkat.AbortCheckEventArgs args) { // application code goes here. }
To add an event handler:
Chilkat.Rss rss = new Chilkat.Rss(); rss.OnAbortCheck += rss_OnAbortCheck;
Chilkat Mono/.NET Core Event Implementation
Event callback implementation:
public void handleAbortCheck(out bool abort) { // application code goes here. }
To add an event handler:
Chilkat.Rss rss = new Chilkat.Rss(); // ... Chilkat.Rss.AbortCheck abortCheck = new Chilkat.Rss.AbortCheck(handleAbortCheck); rss.setAbortCheckCb(abortCheck);
PercentDone
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 true will cause the method to abort and return a failed status (or whatever return value indicates failure).
Chilkat .NET Event Implementation
Args are passed using Chilkat.PercentDoneEventArgs
Event callback implementation:
private void rss_OnPercentDone(object sender, Chilkat.PercentDoneEventArgs args) { // application code goes here. }
To add an event handler:
Chilkat.Rss rss = new Chilkat.Rss(); rss.OnPercentDone += rss_OnPercentDone;
Chilkat Mono/.NET Core Event Implementation
Event callback implementation:
public void handlePercentDone(int pctDone, out bool abort) { // application code goes here. }
To add an event handler:
Chilkat.Rss rss = new Chilkat.Rss(); // ... Chilkat.Rss.PercentDone percentDone = new Chilkat.Rss.PercentDone(handlePercentDone); rss.setPercentDoneCb(percentDone);
ProgressInfo
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.
Chilkat .NET Event Implementation
Args are passed using Chilkat.ProgressInfoEventArgs
Event callback implementation:
private void rss_OnProgressInfo(object sender, Chilkat.ProgressInfoEventArgs args) { // application code goes here. }
To add an event handler:
Chilkat.Rss rss = new Chilkat.Rss(); rss.OnProgressInfo += rss_OnProgressInfo;
Chilkat Mono/.NET Core Event Implementation
Event callback implementation:
public void handleProgressInfo(string name, string value) { // application code goes here. }
To add an event handler:
Chilkat.Rss rss = new Chilkat.Rss(); // ... Chilkat.Rss.ProgressInfo progressInfo = new Chilkat.Rss.ProgressInfo(handleProgressInfo); rss.setProgressInfoCb(progressInfo);
TaskCompleted
Called in the background thread when an asynchronous task completes.
Chilkat .NET Event Implementation
Args are passed using Chilkat.TaskCompletedEventArgs
Event callback implementation:
private void rss_OnTaskCompleted(object sender, Chilkat.TaskCompletedEventArgs args) { // application code goes here. }
To add an event handler:
Chilkat.Rss rss = new Chilkat.Rss(); rss.OnTaskCompleted += rss_OnTaskCompleted;
Chilkat Mono/.NET Core Event Implementation
Event callback implementation:
public void handleTaskIdCompleted(int taskId) { // application code goes here. }
To add an event handler:
Chilkat.Rss rss = new Chilkat.Rss(); // ... Chilkat.Rss.TaskIdCompleted taskIdCompleted = new Chilkat.Rss.TaskIdCompleted(handleTaskIdCompleted); rss.setTaskIdCompletedCb(taskIdCompleted);