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What's new in Win32::OLE

Win32::OLE::NEWS - What's new in Win32::OLE


Win32::OLE::NEWS - What's new in Win32::OLE

This file contains a history of user visible changes to the Win32::OLE::* modules. Only new features and major bug fixes that might affect backwards compatibility are included.

Version 0.11 (changes since 0.1008)

new DHTML typelib browser

The Win32::OLE distribution now contains a type library browser. It is written in PerlScript, generating dynamic HTML. It requires Internet Explorer 4.0 or later. You'll find it in browser/Browser.html. It should be available in the ActivePerl HTML help under Win32::OLE::Browser.

After selecting a library, type or member you can press F1 to call up the corresponding help file at the appropriate location.

VT_DECIMAL support

The Win32::OLE::Variant module now supports VT_DECIMAL variants too. They are not ``officially'' allowed in OLE Automation calls, but even Microsoft's ``ActiveX Data Objects'' sometimes returns VT_DECIMAL values.

VT_DECIMAL variables are stored as 96-bit integers scaled by a variable power of 10. The power of 10 scaling factor specifies the number of digits to the right of the decimal point, and ranges from 0 to 28. With a scale of 0 (no decimal places), the largest possible value is +/-79,228,162,514,264,337,593,543,950,335. With a 28 decimal places, the largest value is +/-7.9228162514264337593543950335 and the smallest, non-zero value is +/-0.0000000000000000000000000001.

Version 0.1008

new LetProperty() object method

In Win32::OLE property assignment using the hash syntax is equivalent to the Visual Basic Set syntax (by reference assignment):

  $Object->{Property} = $OtherObject;

corresponds to this Visual Basic statement:

  Set Object.Property = OtherObject

To get the by value treatment of the Visual Basic Let statement

  Object.Property = OtherObject

you have to use the LetProperty() object method in Perl:

  $Object->LetProperty($Property, $OtherObject);

new HRESULT() function

The HRESULT() function converts an unsigned number into a signed HRESULT error value as used by OLE internally. This is necessary because Perl treats all hexadecimal constants as unsigned. To check if the last OLE function returned ``Member not found'' (0x80020003) you can write:

  if (Win32::OLE->LastError == HRESULT(0x80020003)) {

      # your error recovery here


Version 0.1007 (changes since 0.1005)

OLE Event support

This version of Win32::OLE contains ALPHA level support for OLE events. The userinterface is still subject to change. There are ActiveX objects / controls that don't fire events under the current implementation.

Events are enabled for a specific object with the Win32::OLE->WithEvents() class method:


Please read further documentation in Win32::OLE.

GetObject() and GetActiveObject() now support optional DESTRUCTOR argument

It is now possible to specify a DESTRUCTOR argument to the GetObject() and GetActiveObject() class methods. They work identical to the new() DESTRUCTOR argument.

Remote object instantiation via DCOM

This has actually been in Win32::OLE since 0.0608, but somehow never got documented. You can provide an array reference in place of the usual PROGID parameter to Win32::OLE->new():

  OBJ = Win32::OLE->new([MACHINE, PRODID]);

The array must contain two elements: the name of the MACHINE and the PROGID. This will try to create the object on the remote MACHINE.

Enumerate all Win32::OLE objects

This class method returns the number Win32::OLE objects currently in existance. It will call the optional CALLBACK function for each of these objects:

  $Count = Win32::OLE->EnumAllObjects(sub {

      my $Object = shift;

      my $Class = Win32::OLE->QueryObjectType($Object);

      printf "# Object=%s Class=%s\n", $Object, $Class;


The EnumAllObjects() method is primarily a debugging tool. It can be used e.g. in an END block to check if all external connections have been properly destroyed.

The VARIANT->Put() method now returns the VARIANT object itself

This allows chaining of Put() method calls to set multiple values in an array variant:


The VARIANT->Put(ARRAYREF) form allows assignment to a complete SAFEARRAY

This allows automatic conversion from a list of lists to a SAFEARRAY. You can now write:

  my $Array = Variant(VT_ARRAY|VT_R8, [1,2], 2);

  $Array->Put([[1,2], [3,4]]);

instead of the tedious:





New Variant formatting methods

There are four new methods for formatting variant values: Currency(), Date(), Number() and Time(). For example:

  my $v = Variant(VT_DATE, "April 1 99");

  print $v->Date(DATE_LONGDATE), "\n";

  print $v->Date("ddd',' MMM dd yy"), "\n";

will print:

  Thursday, April 01, 1999

  Thu, Apr 01 99

new Win32::OLE::NLS methods: SendSettingChange() and SetLocaleInfo()

SendSettingChange() sends a WM_SETTINGCHANGE message to all top level windows.

SetLocaleInfo() allows changing elements in the user override section of the locale database. Unfortunately these changes are not automatically available to further Variant formatting; you have to call SendSettingChange() first.

Win32::OLE::Const now correctly treats version numbers as hex

The minor and major version numbers of type libraries have been treated as decimal. This was wrong. They are now correctly decoded as hex.

more robust global destruction of Win32::OLE objects

The final destruction of Win32::OLE objects has always been somewhat fragile. The reason for this is that Perl doesn't honour reference counts during global destruction but destroys objects in seemingly random order. This can lead to leaked database connections or unterminated external objects. The only solution was to make all objects lexical and hope that no object would be trapped in a closure. Alternatively all objects could be explicitly set to undef, which doesn't work very well with exception handling.

With version 0.1007 of Win32::OLE this problem should be gone: The module keeps a list of active Win32::OLE objects. It uses an END block to destroy all objects at program termination before the Perl's global destruction starts. Objects still existing at program termination are now destroyed in reverse order of creation. The effect is similar to explicitly calling Win32::OLE->Uninitialize() just prior to termination.

Version 0.1005 (changes since 0.1003)

Win32::OLE 0.1005 has been release with ActivePerl build 509. It is also included in the Perl Resource Kit for Win32 Update.

optional DESTRUCTOR for GetActiveObject() GetObject() class methods

The GetActiveObject() and GetObject() class method now also support an optional DESTRUCTOR parameter just like Win32::OLE->new(). The DESTRUCTOR is executed when the last reference to this object goes away. It is generally considered impolite to stop applications that you did not start yourself.

new Variant object method: $object->Copy()

See Copy([DIM]) in the Win32::OLE::Variant manpage.

new Win32::OLE->Option() class method

The Option() class method can be used to inspect and modify Module Options in the Win32::OLE manpage. The single argument form retrieves the value of an option:

  my $CP = Win32::OLE->Option('CP');

A single call can be used to set multiple options simultaneously:

  Win32::OLE->Option(CP => CP_ACP, Warn => 3);

Currently the following options exist: CP, LCID and Warn.