How can I associate a file extension with my C application using registry entries?

Associating File Extensions with Applications in C : A Detailed Guide

To enable double-clicking a file associated with your C application and invoking the application with the filename passed as a parameter, creating a registry entry is crucial.

Registry Entry Creation

As outlined in the MSDN article, two key steps are involved:

• Registering the ProgID: The ProgID (file type registry key) holds file type properties, including the icon, description, and context menu options.
• Registering the File Extension: This step assigns a file extension to the ProgID, creating an association between the extension and the file type.

A sample .reg file that demonstrates these steps is as follows:

[HKEY_CURRENT_USER\Software\Classes\blergcorp.blergapp.v1\shell\open\command]
@="c:\path\to\app.exe \""%1"\""
[HKEY_CURRENT_USER\Software\Classes\.blerg]
@="blergcorp.blergapp.v1"

Programmatic Implementation in C

Using the SetValue function in C , you can create the registry keys programmatically:

Registry::SetValue(@"HKEY_CURRENT_USER\Software\Classes\blergcorp.blergapp.v1\shell\open\command", null, @"c:\path\to\app.exe \"%1\"\""), 
Registry::SetValue(@"HKEY_CURRENT_USER\Software\Classes\.blerg", null, "blergcorp.blergapp.v1");

Hive Selection

While examples often suggest setting these keys in HKEY_CLASSES_ROOT, it's recommended to use HKEY_CURRENT_USER to set per-user associations. This ensures that changes made by one user do not affect other users.

Cleanup

Upon application removal, the registry entries created for the file association will remain unless explicitly removed. Consider implementing a registry cleanup mechanism to remove these entries during uninstallation.

Additional Resources

For further details, refer to the following:

• [Best Practices for File Association](https://docs.microsoft.com/en-us/windows/win32/fileassoc/best-practices-for-file-association)
• [File Types and File Association](https://docs.microsoft.com/en-us/windows/win32/fileassoc/file-types-and-file-association)
• [How File Associations Work](https://docs.microsoft.com/en-us/windows/win32/fileassoc/how-file-associations-work)

The above is the detailed content of How can I associate a file extension with my C application using registry entries?. For more information, please follow other related articles on the PHP Chinese website!