Atom Unicode C Reference Documentation
Atom
Current Version: 10.0.0
Represents an Atom document. The Atom API allows one to download, create and modify Atom documents.
Create/Dispose
HCkAtomW instance = CkAtomW_Create(); // ... CkAtomW_Dispose(instance);
Creates an instance of the HCkAtomW object and returns a handle ("void *" pointer). The handle is passed in the 1st argument for the functions listed on this page.
Objects created by calling CkAtomW_Create must be freed by calling this method. A memory leak occurs if a handle is not disposed by calling this function. Also, any handle returned by a Chilkat "C" function must also be freed by the application by calling the appropriate Dispose method, such as CkAtomW_Dispose.
Callback Functions
Provides the opportunity for a method call to be aborted. If TRUE is returned, the operation in progress is aborted. Return FALSE to allow the current method call to continue. This callback function is called periodically based on the value of the HeartbeatMs property. (If HeartbeatMs is 0, then no callbacks are made.) As an example, to make 5 AbortCheck callbacks per second, set the HeartbeatMs property equal to 200.
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 callback is only called 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 methods 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).
This callback counts as an AbortCheck callback, and takes the place of the AbortCheck event when it fires.
The return value indicates whether the method call should be aborted, or whether it should proceed. Return TRUE to abort, and FALSE to proceed.
This is a general callback that provides name/value information about what is happening at certain points during a method call. To see the information provided in ProgressInfo callbacks, if any, write code to handle this event and log the name/value pairs. Most are self-explanatory.
Called in the background thread when an asynchronous task completes. (Note: When an async method is running, all callbacks are in the background thread.)
Properties
AbortCurrent
When set to TRUE, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to FALSE when the next method is called. When the abort occurs, this property is reset to FALSE. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)
topDebugLogFilePath
void CkAtomW_putDebugLogFilePath(HCkAtomW cHandle, const wchar_t *newVal);
const wchar_t *CkAtomW_debugLogFilePath(HCkAtomW cHandle);
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
const wchar_t *CkAtomW_lastErrorHtml(HCkAtomW cHandle);
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
const wchar_t *CkAtomW_lastErrorText(HCkAtomW cHandle);
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
const wchar_t *CkAtomW_lastErrorXml(HCkAtomW cHandle);
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
void CkAtomW_putLastMethodSuccess(HCkAtomW cHandle, BOOL newVal);
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.
topNumEntries
Number of entries in the Atom document.
topVerboseLogging
void CkAtomW_putVerboseLogging(HCkAtomW cHandle, BOOL newVal);
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
const wchar_t *CkAtomW_version(HCkAtomW cHandle);
Methods
AddElement
Adds a new element to the Atom document. The tag is a string such as "title", "subtitle", "summary", etc. Returns the index of the element added, or -1 for failure.
topAddElementDateStr
Adds a new date-formatted element to the Atom document. The tag is a string such as "created", "modified", "issued", etc. The dateTimeStr should be an RFC822 formatted date/time string such as "Tue, 25 Sep 2012 12:25:32 -0500". Returns the index of the element added, or -1 for failure.
topAddElementDt
Adds a new date-formatted element to the Atom document. The tag is a string such as "created", "modified", "issued", etc. Returns the index of the element added, or -1 for failure.
topAddElementHtml
Adds a new HTML formatted element to the Atom document. Returns the index of the element added, or -1 for failure.
topAddElementXHtml
Adds a new XHTML formatted element to the Atom document. Returns the index of the element added, or -1 for failure.
topAddElementXml
Adds a new XML formatted element to the Atom document. Returns the index of the element added, or -1 for failure.
topAddEntry
Adds an "entry" Atom XML document to the caller's Atom document.
topAddLink
Adds a link to the Atom document.
topAddPerson
Adds a person to the Atom document. The tag should be a string such as "author", "contributor", etc. If a piece of information is not known, an empty string or NULL value may be passed.
topDeleteElement
Removes the Nth occurrence of a given element from the Atom document. Indexing begins at 0. For example, to remove the 2nd category, set tag = "category" and index = 1.
topDeleteElementAttr
Remove an attribute from an element.The index should be 0 unless there are multiple elements having the same tag, in which case it selects the Nth occurrence based on the index ( 0 = first occurrence ).
topDeletePerson
Deletes a person from the Atom document. The tag is a string such as "author". The index should be 0 unless there are multiple elements having the same tag, in which case it selects the Nth occurrence based on the index. For example, DeletePerson("author",2) deletes the 3rd author.
topDownloadAtom
Download an Atom feed from the Internet and load it into the Atom object.
Returns TRUE for success, FALSE for failure.
topDownloadAtomAsync (1)
Creates an asynchronous task to call the DownloadAtom method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)
Returns NULL on failure
topGetElement
const wchar_t *CkAtomW_getElement(HCkAtomW cHandle, const wchar_t *tag, int index);
Returns the content of the Nth element having a specified tag.
Returns TRUE for success, FALSE for failure.
topGetElementAttr
const wchar_t *CkAtomW_getElementAttr(HCkAtomW cHandle, const wchar_t *tag, int index, const wchar_t *attrName);
Returns the value of an element's attribute. The element is selected by the tag name and the index (the Nth element having a specific tag) and the attribute is selected by name.
Returns TRUE for success, FALSE for failure.
topGetElementCount
The number of elements having a specific tag.
topGetElementDateStr
const wchar_t *CkAtomW_getElementDateStr(HCkAtomW cHandle, const wchar_t *tag, int index);
Returns an element's value as a date/time in an RFC822 formatted string, such as such as "Tue, 25 Sep 2012 12:25:32 -0500".
Returns TRUE for success, FALSE for failure.
topGetElementDt
GetEntry
GetLinkHref
const wchar_t *CkAtomW_getLinkHref(HCkAtomW cHandle, const wchar_t *relName);
Returns the href attribute of the link having a specified "rel" attribute (such as "service.feed", "alternate", etc.).
Returns TRUE for success, FALSE for failure.
topGetPersonInfo
const wchar_t *CkAtomW_getPersonInfo(HCkAtomW cHandle, const wchar_t *tag, int index, const wchar_t *tag2);
Returns a piece of information about a person. To get the 2nd author's name, call GetPersonInfo("author",1,"name").
Returns TRUE for success, FALSE for failure.
topGetTopAttr
const wchar_t *CkAtomW_getTopAttr(HCkAtomW cHandle, const wchar_t *attrName);
Returns the value of an attribute on the top-level XML node. The tag of a top-level Atom XML node is typically "feed" or "entry", and it might have attributes such as "xmlns" and "xml:lang".
Returns TRUE for success, FALSE for failure.
topHasElement
True (1) if the element exists in the Atom document. Otherwise 0.
topLoadTaskCaller
LoadXml
NewEntry
Initializes the Atom document to be a new "entry".
topNewFeed
Initializes the Atom document to be a new "feed".
topSetElementAttr
Adds or replaces an attribute on an element.
topSetTopAttr
Adds or replaces an attribute on the top-level XML node of the Atom document.
topToXmlString
const wchar_t *CkAtomW_toXmlString(HCkAtomW cHandle);
UpdateElement
Replaces the content of an element.
topUpdateElementDateStr
Replaces the content of a date-formatted element. The index should be an RFC822 formatted date/time string.
topUpdateElementDt
Replaces the content of a date-formatted element.
topUpdateElementHtml
Replaces the content of an HTML element.
topUpdateElementXHtml
Replaces the content of an XHTML element.
topUpdateElementXml
Replaces the content of an XML element.
topUpdatePerson
Replaces the content of a person. To update the 3rd author, call UpdatePerson("author",2,"new name","new URL","new email"). If a piece of information is not known, pass an empty string or a NULL.
top