.NET Control Flow Obfuscator

Control flow obfuscation is a code protection technique that transforms structured control flow constructs (if/else, for, while, foreach, switch) into an unstructured or flattened form that is functionally identical but significantly harder for humans and automated tools to analyze. The most common approach used by commercial .NET obfuscators likeConfuserEx and Dotfuscator is switch-based dispatcher flattening. This converts all control flow into a flat loop with a switch statement and state variable, where each basic block becomes a case in the switch and execution flows between them via state variable updates and continue statements. The result is a single while-true loop containing one large switch that represents the entire function's control flow graph in a flat, hard-to-analyze form.

Our obfuscator scans C# source code using pattern matching to identify control flow structures.if/else chains are detected by pattern-matching the if keyword and capturing the condition expression and body blocks. Each if is converted to a dispatcher case with state transitions. Loops (for, while, foreach, do-while) are detected and wrapped in a dispatcher pattern with loop state management. Switch statementsare identified and marked for flattening. The tool applies transformations in order: if/else flattening first, then loops, then switch statements. Each transformation preserves the original code's logic while restructuring its control flow into the flattened dispatcher form. Configurable options let you control the depth of flattening and the label style used for block identifiers.All processing is done client-side. No code is uploaded to any server.

This tool has important limitations. It does not produce fully obfuscated assemblies- it transforms C# source code at the text level. Professional obfuscators like ConfuserEx operate at the IL (Intermediate Language) level after compilation, enabling more advanced transforms.Try/catch/finally blocks are not currently flattened due to their complexity with exception handling semantics. Nested lambda expressions and LINQ queries may not be fully flattened. The obfuscated output should be tested thoroughly before production use to ensure the dispatcher pattern does not introduce performance regressions. Always verify that the obfuscated code compiles and behaves identically to the original.

This tool runs entirely in your browser using client-side JavaScript. The C# source code you paste, all detected control flow structures, and the obfuscated output are never uploaded to any server, stored in any database, or transmitted over the network. All parsing, structure detection, and transformation execute locally on your device. There are no API calls, analytics tracking, cookies, or data collection of any kind. This makes it completely safe for obfuscating proprietary C# code, commercial applications, trade secret algorithms, or sensitive business logic without exposing it to third parties.