How to safely mask and share C# code

When this guide is useful

Users looking for ways to mask, anonymize, or replace sensitive information in C# code can learn how to safely share it to reviewers or generating AI while preserving its structure.

• Paste the C# code to the generation AI and consult the cause of the error
• Share defect reproduction code with external vendors or other teams
• Replace unique information before posting to question sites or external reviews

Confidential information that tends to remain in C# code

• Additional information for this feature.
• Connection strings, configuration keys, endpoints, exception messages
• Comments and log messages including customer name, product name, and environment name
• String containing internal URL, IP address, file path, and authentication information

Steps to mask while preserving structure

1. Enter only what you need to share and decide on a policy for leaving comments and values.
2. Additional information for this feature.
3. Verify that namespaces, attributes, generics, and LINQ correspondences are readable after masking.
4. Right-click on the result side, remove only the parts necessary for the explanation, and do a final check.

分享前需要检查的要点

Even if you replace just the identifier, it may be possible to infer the system or customer from connection strings, configuration keys, endpoints, and exception messages. Please also check that the same original value has the same kana.

Check for the same information in any logs, configuration files, or screenshots you share with your code.

Masking results do not guarantee that C# will compile or run. Visually check syntax and dependencies before sharing.

Concrete example: Sharing an ASP.NET service class for investigation

ASP.NET service classes may contain multiple types of information at the same time, such as identifiers, connection destinations, log statements, and fixed values. First, remove peripheral code that is unnecessary for explanation.

Additional information: LINQ 々

1. Copy
2. Select
3. Execute masking and check whether the original information remains and the structure collapses.
4. Remove only the parts necessary for the explanation and paste it to the shared destination.

Just before sending to the shared destination, please search for any part of the company name, domain, path, or email address to check if it is still valid.

Frequently asked questions

Is the C# code sent to the server?

Input

Can I just run the code after masking?

Although maintaining the structure is a priority, complete parsing and build success are not guaranteed, so please check in another environment if necessary.