HtmlToXml DataFlex Reference Documentation

HtmlToXml

Class for converting HTML to well-formed XML for the purpose of programmatically extracting (scraping) information from any HTML page.

Object Creation

Handle hoHtmlToXml
Get Create(RefClass(cComHtmlToXml)) to hoHtmlToXml

Properties

Function ComDebugLogFilePath Returns String
Procedure Set ComDebugLogFilePath String value

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.

Function ComDropCustomTags Returns Boolean
Procedure Set ComDropCustomTags Boolean value

If set to true, then any non-standard HTML tags will be dropped when converting to XML.

Function ComHtml Returns String
Procedure Set ComHtml String value

The HTML to be converted by the ToXml method. To convert HTML to XML, first set this property to the HTML string and then call ToXml. The ConvertFile method can do file-to-file conversions.

Function ComLastBinaryResult Returns Variant

Introduced in version 9.5.0.52

The binary data returned by the last (binary data returning) method called. Only available if Chilkat.Global.KeepBinaryResult is set to True. This provides a means for obtaining large varbinary results in the SQL Server environment (where limitations exist in getting large amounts of data returned by method calls, but where temp tables can be used for binary properties).

Function ComLastErrorHtml Returns String

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.

Function ComLastErrorText Returns String

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.

Concept of LastErrorText

LastErrorText Standard Information

Function ComLastErrorXml Returns String

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.

Function ComLastMethodSuccess Returns Boolean
Procedure Set ComLastMethodSuccess Boolean value

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.

Function ComLastStringResult Returns String

Introduced in version 9.5.0.52

The string return value of the last (string returning) method called. Only available if Chilkat.Global.KeepStringResult is set to True. This provides a means for obtaining large string results in the SQL Server environment (where limitations exist in getting long strings returned by method calls, but where temp tables can be used for string properties).

Long Strings Returned by ActiveX Methods in SQL Server

Function ComLastStringResultLen Returns Integer

Introduced in version 9.5.0.53

The length, in characters, of the string contained in the LastStringResult property.

Function ComNbsp Returns Integer
Procedure Set ComNbsp Integer value

Determines how to handle   HTML entities. The default value, 0 will cause   entites to be convert to normal space characters (ASCII value 32). If this property is set to 1, then  's will be converted to &#160. If set to 2, then &nbps;'s are dropped. If set to 3, then &nbsp's are left unmodified.

Function ComVerboseLogging Returns Boolean
Procedure Set ComVerboseLogging Boolean value

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.

Function ComVersion Returns String

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

Function ComXmlCharset Returns String
Procedure Set ComXmlCharset String value

The charset, such as "utf-8" or "iso-8859-1" of the XML to be created. If XmlCharset is empty, the XML is created in the same character encoding as the HTML. Otherwise the HTML is converted XML and converted to this charset.

Methods

Function ComConvertFile String inHtmlPath String destXmlPath Returns Boolean

Converts an HTML file to a well-formed XML file that can be parsed for the purpose of programmatically extracting information.

Returns True for success, False for failure.

Procedure ComDropTagType String tagName

Allows for any specified tag to be dropped from the output XML. To drop more than one tag, call this method once for each tag type to be dropped.

Procedure ComDropTextFormattingTags

Causes text formatting tags to be dropped from the XML output. Text formatting tags are: b, font, i, u, br, center, em, strong, big, tt, s, small, strike, sub, and sup.

Function ComIsUnlocked Returns Boolean

Returns True if the component is already unlocked. Otherwise returns False.

Function ComReadFile String path Returns Variant

Convenience method for reading a complete file into a byte array.

Returns null on failure

Function ComReadFileToString String filename String srcCharset Returns String

Convenience method for reading a text file into a string. The character encoding of the text file is specified by srcCharset. Valid values, such as "iso-8895-1" or "utf-8" are listed at: List of Charsets.

Returns null on failure

Procedure ComSetHtmlBytes Variant inData

Sets the Html property from a byte array.

Function ComSetHtmlFromFile String filename Returns Boolean

Sets the Html property by loading the HTML from a file.

Returns True for success, False for failure.

Function ComToXml Returns String

Converts the HTML in the "Html" property to XML and returns the XML string.

Returns null on failure

Convert an HTML Table to Plain-Text

Procedure ComUndropTagType String tagName

Causes a specified type of tag to NOT be dropped in the output XML.

Procedure ComUndropTextFormattingTags

Causes text formatting tags to NOT be dropped from the XML output. Text formatting tags are: b, font, i, u, br, center, em, strong, big, tt, s, small, strike, sub, and sup.

Important: Text formatting tags are dropped by default. Call this method to prevent text formatting tags from being dropped.

Function ComUnlockComponent String unlockCode Returns Boolean

Unlocks the component. An arbitrary unlock code may be passed to automatically begin a 30-day trial.

Returns True for success, False for failure.

Diagnosing UnlockComponent Problems

UnlockComponent LastErrorText shows exact string passed to it.

Verify UnlockComponent Success w/ Purchased Unlock Code

LastErrorText Standard Information

Function ComWriteFile String path Variant fileData Returns Boolean

Convenience method for saving a byte array to a file.

Returns True for success, False for failure.

Function ComWriteStringToFile String stringToWrite String filename String charset Returns Boolean

Convenience method for saving a string to a file. The character encoding of the output text file is specified by charset (the string is converted to this charset when writing). Valid values, such as "iso-8895-1" or "utf-8" are listed at: List of Charsets.

Returns True for success, False for failure.