CkRss Ruby Reference Documentation

CkRss

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

obj = Chilkat::CkRss.new()

Properties

# strVal is a string
# ckStr is a CkString
rss.get_DebugLogFilePath(ckStr);
strVal = rss.debugLogFilePath();
rss.put_DebugLogFilePath(strVal);

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.

# strVal is a string
# ckStr is a CkString
rss.get_LastErrorHtml(ckStr);
strVal = rss.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.

# strVal is a string
# ckStr is a CkString
rss.get_LastErrorText(ckStr);
strVal = rss.lastErrorText();

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.

# strVal is a string
# ckStr is a CkString
rss.get_LastErrorXml(ckStr);
strVal = rss.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.

# boolVal is a boolean
boolVal = rss.get_LastMethodSuccess();
rss.put_LastMethodSuccess(boolVal);

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.

# intVal is an integer
intVal = rss.get_NumChannels();

The number of channels in the RSS document.

# intVal is an integer
intVal = rss.get_NumItems();

The number of items in the channel.

# boolVal is a boolean
boolVal = rss.get_Utf8();
rss.put_Utf8(boolVal);

When set to true, all "const char *" arguments are interpreted as utf-8 strings. If set to false (the default), then "const char *" arguments are interpreted as ANSI strings. Also, when set to true, and Chilkat method returning a "const char *" is returning the utf-8 representation. If set to false, all "const char *" return values are ANSI strings.

# boolVal is a boolean
boolVal = rss.get_VerboseLogging();
rss.put_VerboseLogging(boolVal);

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.

# strVal is a string
# ckStr is a CkString
rss.get_Version(ckStr);
strVal = rss.version();

Version of the component/library, such as "9.4.1.42"

Methods

# returns a CkRss
ret_rss = rss.AddNewChannel();

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

# returns a CkRss
ret_rss = rss.AddNewImage();

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

# returns a CkRss
ret_rss = rss.AddNewItem();

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

# url is a string
status = rss.DownloadRss(url);

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

Returns true for success, false for failure.

Example: Read RSS Feed

# returns a CkTask
# url is a string
ret_task = rss.DownloadRssAsync(url);

Creates an asynchronous task to call the DownloadRss method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

How to Run an Asynchronous Task

# tag is a string
# attrName is a string
# outStr is a CkString (output)
status = rss.GetAttr(tag, attrName, outStr);
retStr = rss.getAttr(tag, 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 true for success, false for failure.

# returns a CkRss
# index is an integer
ret_rss = rss.GetChannel(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.

# tag is a string
retInt = rss.GetCount(tag);

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

# tag is a string
# outStr is a CkString (output)
status = rss.GetDateStr(tag, outStr);
retStr = rss.getDateStr(tag);

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

Returns true for success, false for failure.

# returns a CkRss
ret_rss = rss.GetImage();

Return the image associated with the channel.

# tag is a string
retInt = rss.GetInt(tag);

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

# returns a CkRss
# index is an integer
ret_rss = rss.GetItem(index);

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

# tag is a string
# outStr is a CkString (output)
status = rss.GetString(tag, outStr);
retStr = rss.getString(tag);

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

Returns true for success, false for failure.

# filePath is a string
status = rss.LoadRssFile(filePath);

Load an RSS document from a file.

Returns true for success, false for failure.

# rssString is a string
status = rss.LoadRssString(rssString);

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

Returns true for success, false for failure.

# tag is a string
# index is an integer
# attrName is a string
# outStr is a CkString (output)
status = rss.MGetAttr(tag, index, attrName, outStr);
retStr = rss.mGetAttr(tag, index, 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 true for success, false for failure.

# tag is a string
# index is an integer
# outStr is a CkString (output)
status = rss.MGetString(tag, index, outStr);
retStr = rss.mGetString(tag, index);

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

Returns true for success, false for failure.

# tag is a string
# idx is an integer
# attrName is a string
# value is a string
status = rss.MSetAttr(tag, idx, attrName, value);

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

Returns true for success, false for failure.

# tag is a string
# idx is an integer
# value is a string
status = rss.MSetString(tag, idx, value);

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

Returns true for success, false for failure.

rss.NewRss();

Clears the RSS document.

# tag is a string
rss.Remove(tag);

Removes a sub-element from the RSS document.

# path is a string
status = rss.SaveLastError(path);

Saves the last-error information (the contents of LastErrorXml) to an XML formatted file.

Returns true for success, false for failure.

# tag is a string
# attrName is a string
# value is a string
rss.SetAttr(tag, attrName, value);

Sets the value of a sub-element attribute.

# tag is a string
rss.SetDateNow(tag);

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

# tag is a string
# dateTimeStr is a string
rss.SetDateStr(tag, dateTimeStr);

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

# tag is a string
# value is an integer
rss.SetInt(tag, value);

Sets the value of an integer sub-element.

# tag is a string
# value is a string
rss.SetString(tag, value);

Sets the value of a sub-element.

# outStr is a CkString (output)
status = rss.ToXmlString(outStr);
retStr = rss.toXmlString();

Returns the RSS document as an XML string.

Returns true for success, false for failure.