Programming PHP

This creates a reference (VT_BYREF) to a 32-bit integer (VT_I4) with an initial value of
0. PHP can pass strings and numbers to COM servers automatically, but VARIANT
COM types are required whenever you need to pass arguments by reference.
For most OLE automation, the most difficult task is that of converting a VB method
call to something similar in PHP. For instance, this is VBScript to insert text into a
Word document:
Selection.TypeText Text:="This is a test"
The same line in PHP is:
$word->Selection->Typetext("This is a test");
It is important to note two quirks in PHP’s present COM support. First, you cannot
pass parameters in the middle of an object method. So instead of writing a method
as:
$a->b(p1)->c(p2)
you must break up the method as:
$tmp=$a->b(p1);$tmp->c(p2);
Second, PHP is unaware of default parameters from Microsoft OLE applications
such as Word. This simply means that you must explicitly pass all values to the
underlying COM object.
Determining the API
To determine object hierarchy and parameters for a product such as Word, you
might visit the Microsoft developer’s site at http://msdn.microsoft.com/library/default.
asp?url=/library/en-us/vbawd10/html/wotocObjectModelApplication.asp and search
for the specification for the Word object that interests you. Another alternative is to
use both Microsoft’s online VB scripting help and Word’s supported macro language.
Using these together will allow you to understand the order of parameters, as
well as the desired values for a given task.
For instance, assuming we want to understand how a simple find and replace works,
we can do the following:
1. Open Word and create a new document containing some sample text. For
example:
"This is a test, 123"
2. Record a macro to find the text “test” and replace it with the text “rest”. Do this
by selecting Tools ➝ Macro ➝ Record New Macro from Word’s menu bar. Once
recording, use search and replace to create the macro. We will use this macro,
shown in Figure 15-2, to determine the values of parameters that we will pass in
our PHP COM method.
3. Use Word’s object browser to determine the calling syntax for all parameters in
this example. Press Alt-F11 to access Word’s VBScript online help, then type in the
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Interfacing with COM | 361