HtmlToText Chilkat2 Perl Reference Documentation

Chilkat2::HtmlToText

Current Version: 11.7.0

Markdown version of this page for AI tools (v 11.7.0) · all AI docs

Chilkat.HtmlToText

Convert HTML into readable plain text with control over links, wrapping, and encoding.

Chilkat.HtmlToText converts HTML content into readable plain text. It can decode HTML entities, wrap output at a configurable right margin, optionally include or suppress hyperlink URLs, convert HTML supplied as a string or StringBuilder, and read or write files using an explicit character encoding.

HTML to plain text

Convert HTML markup into readable text suitable for display, logging, indexing, email alternatives, or text-only output.

Entity decoding

Decode HTML entities so text such as named entities and numeric character references becomes normal readable output.

Line wrapping

Use RightMargin to wrap text at a chosen width, or set it to 0 when no right-margin wrapping is wanted.

Link handling

Suppress hyperlink URLs for cleaner text, or emit URLs when the output needs to preserve the destination of HTML links.

StringBuilder support

Convert HTML directly from a StringBuilder when working with larger or incrementally built HTML content.

File and charset helpers

Read HTML from files and write text output using a specified character encoding.

Common pattern: Provide the HTML as a string, file, or StringBuilder, choose whether to decode entities and include link URLs, set the desired right margin, then convert the result to plain text. Use HtmlToText when the goal is readable text, not structured XML or DOM-style parsing.

Object Creation

use Chilkat2;

my $htmlToText = Chilkat2::HtmlToText->new;
# or set properties (and RaiseError) at creation:
# my $htmlToText = Chilkat2::HtmlToText->new(VerboseLogging => 1, RaiseError => 1);
my $htmlToText = Chilkat2::HtmlToText->new(Property => $value, ...);

Creates the object. The optional pairs set writable properties (and RaiseError) in order, as if set one by one; an unknown or read-only name croaks. use Chilkat2; loads every class; the Chilkat2/HtmlToText.pm file holds only this class's documentation (perldoc Chilkat2::HtmlToText).

Perl frees the object when its last reference goes (undef $htmlToText, or the variable going out of scope); there is nothing to close. Objects returned by methods are independent and freed the same way. The class may be subclassed (use parent -norequire, 'Chilkat2::HtmlToText';): an object is a blessed hash reference whose hash is free for the subclass's own fields.

my $boolVal = $htmlToText->RaiseError;
$htmlToText->RaiseError($boolVal);

When false (the default), a method that fails returns false (or undef), and the reason is in LastErrorText. When true, it dies with a Chilkat2::Error instead, as DBI does with its RaiseError. Objects returned by a method inherit the value of the object that returned them.

Errors

A Chilkat2::Error stringifies to the failed call's full LastErrorText, and has the methods text, class ('Chilkat2::HtmlToText'), method (the method name) and object. Methods that look something up and find nothing return undef without dying (each such method says so), methods that answer a question (HasMember, IsUnlocked, ...) return a plain boolean, and property reads and writes never fail for Chilkat reasons.

Misuse always croaks, with your file and line, whatever RaiseError is: a wrong number of arguments, a reference or undef where a string or number is expected, an object of the wrong class, an out-of-range integer, a string containing a NUL character, a wide character in a byte string, or a write to a read-only property.

Strings are Perl character strings in both directions (length, regexes and :encoding layers see characters); binary data (BinData) is a byte string. Unlocking: call Chilkat2::Global->new->UnlockBundle('...') once at startup.

Properties

DebugLogFilePath
# $strVal is a string
my $strVal = $htmlToText->DebugLogFilePath;
$htmlToText->DebugLogFilePath($strVal);

If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.

Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.

Possible causes of hangs include:

  • A timeout property set to 0, indicating an infinite timeout.
  • A hang occurring within an event callback in the application code.
  • An internal bug in the Chilkat code causing the hang.

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DecodeHtmlEntities
# $boolVal is a boolean
my $boolVal = $htmlToText->DecodeHtmlEntities;
$htmlToText->DecodeHtmlEntities($boolVal);

Controls whether HTML character references are decoded when converting HTML to plain text. The default value is 1.

Value Behavior
1 HTML entities and numeric character references are decoded to their corresponding characters. For example, & becomes &.
0 Character references are left encoded in the plain-text output.
Typical use: Leave this property set to 1 when the goal is human-readable text. Set it to 0 when the original entity notation itself must be preserved.

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LastErrorHtml
# $strVal is a string (read-only)
my $strVal = $htmlToText->LastErrorHtml;

Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastErrorText
# $strVal is a string (read-only)
my $strVal = $htmlToText->LastErrorText;

Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastErrorXml
# $strVal is a string (read-only)
my $strVal = $htmlToText->LastErrorXml;

Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

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LastMethodSuccess
# $boolVal is a boolean
my $boolVal = $htmlToText->LastMethodSuccess;
$htmlToText->LastMethodSuccess($boolVal);

Indicates the success or failure of the most recent method call: 1 means success, 0 means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.

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RightMargin
# $intVal is an integer
my $intVal = $htmlToText->RightMargin;
$htmlToText->RightMargin($intVal);

Controls line wrapping in the generated plain text. The default value is 80. As a line approaches the configured margin, Chilkat attempts to wrap at a SPACE character. Set this property to 0 to disable right-margin wrapping.

Soft margin: The right margin is a preferred wrapping point, not a guaranteed maximum line length. A long sequence with no suitable SPACE character may extend beyond the configured margin.

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SuppressLinks
# $boolVal is a boolean
my $boolVal = $htmlToText->SuppressLinks;
$htmlToText->SuppressLinks($boolVal);

Controls whether hyperlink destination URLs are included in the generated plain text. The default value is 1.

Value Behavior
1 The visible anchor text is retained, but hyperlink destination URLs are omitted.
0 Hyperlink URLs are included. By default, they are collected in a References: section at the end of the plain text.
For example, with SuppressLinks set to 0, an HTML link whose visible text is chilkat and whose URL is https://www.chilkatsoft.com/ produces the visible text and a numbered reference at the end of the output.
Related options: When link URLs are enabled, UncommonOptions can be used to suppress the trailing references list with NoReferencesList or emit URLs inline with EmitUrls.

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UncommonOptions
# $strVal is a string
my $strVal = $htmlToText->UncommonOptions;
$htmlToText->UncommonOptions($strVal);
Introduced in version 11.0.0

Specifies uncommon HTML-to-text conversion options as a comma-separated list of keywords. The default is the empty string, which is appropriate for normal use.

Keyword Effect
NoReferencesList Does not generate the hyperlink-reference list at the end of the plain-text output.
EmitUrls Emits hyperlink URLs inline in the plain-text output instead of relying on the default trailing reference list.
Interaction with SuppressLinks: These options control the presentation of hyperlink URLs when URL output is enabled. If SuppressLinks is 1, hyperlink URLs are suppressed.

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VerboseLogging
# $boolVal is a boolean
my $boolVal = $htmlToText->VerboseLogging;
$htmlToText->VerboseLogging($boolVal);

If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

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Version
# $strVal is a string (read-only)
my $strVal = $htmlToText->Version;

Version of the component/library, such as "10.1.0"

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Methods

ToText
# $html is a string
# $str is a string or undef
my $str = $htmlToText->ToText($html);

Converts the HTML in html to readable plain text and returns the result. The conversion honors DecodeHtmlEntities, RightMargin, SuppressLinks, and UncommonOptions. HTML markup is interpreted to produce readable text rather than simply being removed with a tag-stripping operation.

Plain-text conversion: The output is intended for reading, indexing, logging, email text alternatives, and similar text-oriented uses. It is not intended to preserve the original HTML markup or visual layout exactly.

Returns undef on failure; LastErrorText says why. With RaiseError on, a failure dies with a Chilkat2::Error instead (it stringifies to the LastErrorText); the object remains usable either way.

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ToTextSb
# $sb is a Chilkat2::StringBuilder
# $success is true or false
my $success = $htmlToText->ToTextSb($sb);
Introduced in version 9.5.0.97

Converts the HTML currently contained in sb to plain text in place. On success, the same StringBuilder contains the converted plain-text result. The conversion honors DecodeHtmlEntities, RightMargin, SuppressLinks, and UncommonOptions.

StringBuilder workflow: Use this method when the HTML is already held in a StringBuilder and you want the conversion result returned through that same object rather than as a separate string.

Returns true on success, false on failure; LastErrorText says why. With RaiseError on, a failure dies with a Chilkat2::Error instead (it stringifies to the LastErrorText); the object remains usable either way.

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