Xmp DataFlex Reference Documentation

Xmp

Chilkat XMP is a software component (SDK, toolkit, library, etc) for accessing, manipulating, and adding XMP metadata to JPEG and TIFF files.

Object Creation

Handle hoXmp
Get Create(RefClass(cComChilkatXmp)) to hoXmp

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 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.

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 ComNumEmbedded Returns Integer

The number of XMP metadata documents found within the JPG or TIFF file loaded by LoadAppFile.

Function ComStructInnerDescrip Returns Boolean
Procedure Set ComStructInnerDescrip Boolean value

Determines whether structures are stored with rdf:parseType="Resource", or within an "rdf:Description" sub-node.

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 "9.4.1.42"

Methods

Function ComAddArray cComChilkatXml xml String arrType String propName cComCkStringArray values Returns Boolean

Adds or replaces an XMP property array. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The 2nd argument specifies the array type, which can be "bag", "seq", or "alt". The property name should be prefixed with the namespace, such as "dc:subject".

XMP Array Property - Bag, Seq, or Alt

Procedure ComAddNsMapping String ns String uri

Adds a namespace to URI mapping. When a property is added via AddSimpleString or any of the other methods, the property name is namespace qualified. When adding the first property in a namespace, the rdf:Description is automatically added and the URI is obtained from the namespace-to-URI mappings. The standard (and commonly used) namespace mappings are defined by default. This is only used if the namespace is custom or not already handled.

Function ComAddSimpleDate cComChilkatXml iXml String propName DateTime propVal Returns Boolean

This method is deprecated. It will be removed in a future version.

Adds or replaces an XMP date property. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The property name should be prefixed with the namespace, such as "xap:CreateDate".

Function ComAddSimpleInt cComChilkatXml iXml String propName Integer propVal Returns Boolean

Adds or updates an XMP integer property. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The property name should be prefixed with the namespace, such as "tiff:XResolution".

Function ComAddSimpleStr cComChilkatXml iXml String propName String propVal Returns Boolean

Adds or updates a simple XMP string property. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The property name should be prefixed with the namespace, such as "photoshop:Credit".

Function ComAddStructProp cComChilkatXml iChilkatXml String structName String propName String propValue Returns Boolean

Adds or updates an XMP structured property value. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The structure name should be prefixed with the namespace, such as "Iptc4xmpCore:CreatorContactInfo". The property name within the structure should also be prefixed with the namespace, such as "Iptc4xmpCore:CiAdrCity".

Function ComAppend cComChilkatXml iXml Returns Boolean

Appends a new XMP metadata file to the XMP object. Any XMPs appended via this method will be present in the file when SaveAppFile is called. Files containing XMP metadata typically only include a single XMP document, so this method is usually only called when adding XMP metadata to a file for the first time.

Function ComDateToString DateTime d Returns String

This method is deprecated. It will be removed in a future version.

Converts a date to a string representation. This method is added for convenience (just in case date-to-string conversions are required).

Returns True for success, False for failure.

Function ComGetArray cComChilkatXml iXml String propName Returns cComCkStringArray

Finds and returns an XMP array property. The property name should be prefixed with the namespace, such as "dc:subject".

Function ComGetEmbedded Integer index Returns cComChilkatXml

Returns the Nth embedded XMP document as a Chilkat XML object.

Function ComGetProperty cComChilkatXml iXml String propName Returns cComChilkatXml

To be documented soon...

Function ComGetSimpleDate cComChilkatXml iXml String propName Returns DateTime

This method is deprecated. It will be removed in a future version.

Finds and returns an XMP date property. The property name should be prefixed with the namespace, such as "xap:ModifyDate".

Returns True for success, False for failure.

Function ComGetSimpleInt cComChilkatXml iXml String propName Returns Integer

Finds and returns an XMP integer property. The property name should be prefixed with the namespace, such as "tiff:ResolutionUnit".

Function ComGetSimpleStr cComChilkatXml iXml String propName Returns String

Finds and returns an XMP simple string property. The property name should be prefixed with the namespace, such as "photoshop:Source".

Returns True for success, False for failure.

Get a String Property Value from XMP

Function ComGetStructPropNames cComChilkatXml iXml String structName Returns cComCkStringArray

Returns the property names used by an exsting structure within an XMP document. The contents of the structure can be retrieved by calling GetStructValue for each property name returned by GetStructPropNames.

Function ComGetStructValue cComChilkatXml iXml String structName String propName Returns String

Returns the value of a single item within an XMP structure property. Property names should always be prefixed with the namespace.

Returns True for success, False for failure.

Get a Structure Property Value from XMP

Function ComLoadAppFile String filename Returns Boolean

Loads a TIFF or JPG file into the XMP object.

Function ComLoadFromBuffer Variant fileData String ext Returns Boolean

Loads a JPG or TIFF from an byte buffer containing the image file data.

Function ComNewXmp Returns cComChilkatXml

Creates and returns a new/empty XMP metadata document as a Chilkat XML object.

Add XMP MetaData to JPG or TIFF

Function ComRemoveAllEmbedded Returns Boolean

Removes all XMP metadata documents from an XMP object. After calling this method, call SaveAppFile to rewrite the JPG or TIFF file with the XMP metadata removed.

Returns True for success, False for failure.

Function ComRemoveArray cComChilkatXml iXml String propName Returns Boolean

Removes an XMP array property from the XMP document.

Function ComRemoveEmbedded Integer index Returns Boolean

Removes a single XMP metadata document from the JPG or TIFF file. Call SaveAppFile to persist the changes to disk.

Returns True for success, False for failure.

Procedure ComRemoveNsMapping String ns

Removes a namespace-to-URI mapping.

Function ComRemoveSimple cComChilkatXml iXml String propName Returns Boolean

Removes a simple XMP property from the XMP document.

Function ComRemoveStruct cComChilkatXml iXml String structName Returns Boolean

Removes an XMP structure property from the XMP document.

Function ComRemoveStructProp cComChilkatXml iXml String structName String propName Returns Boolean

Removes a single member from an XMP structured property.

Function ComSaveAppFile String filename Returns Boolean

Persists all changes made to the XMP document(s) by saving the XMP object to a file. Changes made by adding, updating, or removing properties are not persisted to the filesystem until this is called.

Function ComSaveToBuffer Returns Variant

Saves a JPG or TIFF image with updated XMP to a byte buffer.

Returns True for success, False for failure.

Function ComStringToDate String str Returns DateTime

This method is deprecated. It will be removed in a future version.

Converts a string to a date value. This method is added for convenience (just in case string-to-date conversions are required).

Returns True for success, False for failure.

Function ComUnlockComponent String unlockCode Returns Boolean

Unlocks the XMP component at runtime. This must be called once at the beginning of your application. Passing an arbitrary value initiates a fully-functional 30-day trial. A permanent unlock code is required to use the component beyond 30 days.

Diagnosing UnlockComponent Problems

UnlockComponent LastErrorText shows exact string passed to it.

Verify UnlockComponent Success w/ Permanent Unlock Code

LastErrorText Standard Information