The ‘assoc’ command is a Windows command-line utility that allows users to view or modify the associations between file extensions and file types. It is especially helpful when dealing with file associations and can be used to display the associated file type for a specific extension, set the associated file type for a specific extension, or view all associations between file extensions and file types.

Use case 1: List all associations between file extensions and file types

Code:

assoc

Motivation: This use case is useful when you want to view all the associations between file extensions and file types on your system. It can be helpful in identifying the default file types for various extensions.

Explanation: The ‘assoc’ command is used without any arguments to list all associations between file extensions and file types. It retrieves the information from the registry and displays the file extension along with the associated file type.

Example Output:

.txt=txtfile
.jpg=jpegfile
.docx=Word.Document.12

Use case 2: Display the associated file type for a specific extension

Code:

assoc .txt

Motivation: This use case is useful when you want to quickly check the file type associated with a specific file extension. It can be handy when troubleshooting file association issues or confirming the default file type for a particular extension.

Explanation: In this use case, the ‘assoc’ command is followed by the file extension for which you want to display the associated file type. In the example, ‘.txt’ is provided, so the command will return the file type associated with the ‘.txt’ extension.

Example Output:

.txt=txtfile

Use case 3: Set the associated file type for a specific extension

Code:

assoc .txt=txtfile

Motivation: This use case is helpful when you want to manually set the associated file type for a specific file extension. It can be useful when you want to change the default program used to open files with a particular extension.

Explanation: In this use case, the ‘assoc’ command is used with the file extension and the desired file type separated by an equals sign. The example command sets the file type for the ‘.txt’ extension to ’txtfile’.

Example Output (no output is displayed if the command is successful):

Use case 4: View the output of ‘assoc’ one screen at a time

Code:

assoc | more

Motivation: This use case is useful when there are many associations between file extensions and file types, and the output exceeds the size of the command prompt window. Using the ‘more’ command allows you to view the output one screen at a time, making it easier to read and navigate through the information.

Explanation: In this use case, the ‘assoc’ command is piped to the ‘more’ command using the pipe symbol (|). The output of the ‘assoc’ command is then displayed one screen at a time by pressing the Enter key.

Example Output:

.txt=txtfile
.jpg=jpegfile
.docx=Word.Document.12
Press Enter to continue...

Conclusion:

The ‘assoc’ command is a versatile tool for managing file associations in Windows, allowing users to view and modify the associations between file extensions and file types. By using the various use cases provided, you can easily retrieve information about file associations and make changes as needed. Whether you need to view all associations, check the associated file type for a specific extension, set a file type, or view the output one screen at a time, the ‘assoc’ command proves to be a valuable utility.