dotPeek can identify local source code based on PDB files or fetch source code from source servers such as Microsoft Reference Source Center or SymbolSource.org.
Unmanaged DLLs compile directly into x86 or x64 machine architecture assembly code. During this process, variable names, comments, and structure definitions are completely stripped away. An online decompiler processing an unmanaged DLL will usually output or a highly abstracted, hard-to-read approximation of C code. Top Online DLL Decompilers and Reverse Engineering Tools dll decompiler online