Pywin32技术问询：如何访问数据句柄指向的目标数据？

Let's break down how to work with that property handle you're seeing from EnumPropsEx.

First, a quick clarification: when you use EnumPropsEx, the x parameter in your callback function is actually the property value tied to the property name (the prop parameter). For window properties set via SetPropW, this value can be a handle, a memory pointer, or a simple integer—exactly what you're seeing with 2621596 for the fpTextTip property.

Step 1: Fetch the Value Directly with GetProp #

Instead of enumerating all properties to find the one you want, you can target it directly using win32gui.GetProp—it's a cleaner approach:

import win32gui

hwnd = 1574574
target_prop = "fpTextTip"
prop_value = win32gui.GetProp(hwnd, target_prop)
print(f"Value for {target_prop}: {prop_value}")

This will return the same handle you saw in your EnumPropsEx output, but cuts out the extra enumeration steps.

Step 2: Figure Out What the Handle Represents #

The hard part here is that this handle is application-specific (tied to your Visual Studio C++ app). It's likely one of three things:

• A pointer to a custom C++ struct/object defined by the app
• A standard system handle (like a child window HWND, font HFONT, or brush HBRUSH)
• A user-defined integer flag

Since this is a Visual Studio-related window, fpTextTip is almost certainly linked to the IDE's text tooltip system.

Step 3: Access the Data Behind the Handle #

Your options depend on what type of handle it is:

1. Test for standard system handles
   You can check if it's a known system handle type using simple win32gui functions:

   # Check if it's a valid window handle
   if win32gui.IsWindow(prop_value):
       print("This is a child window handle!")
       print(f"Window text: {win32gui.GetWindowText(prop_value)}")
   
   # You could also test for font handles, brushes, etc., with similar functions
   

2. Inspect memory with a debugger
   If it's a pointer to a custom struct, you'll need to attach a debugger (like WinDbg or Visual Studio) to the target app:

   • Get the process ID (PID) of your app using win32gui.GetWindowThreadProcessId(hwnd)
   • Attach the debugger to that PID
   • Dump the memory at the address the handle points to
   • Reverse-engineer the struct layout (this requires C++ knowledge and familiarity with the app's internals)

3. Leverage public symbols or documentation
   For Visual Studio-specific properties, Microsoft sometimes publishes symbol files or internal API docs. Loading Visual Studio's symbols in WinDbg can give you context about what fpTextTip references.

Critical Notes #

• Window properties are tied to the process that set them. You can't directly dereference a pointer from another process in Python—you'll need to use inter-process memory reading functions like win32api.ReadProcessMemory if you want to access the data from your Python script.
• If the property is a memory pointer, its address is only valid within the target app's address space. Using it directly in your Python process will cause crashes or errors.

内容的提问来源于stack exchange，提问作者mired