From command line creating exe, dll ....

• Compiles File.cs producing File.exe: csc File.cs
• Compiles File.cs producing File.dll: csc /target:library File.cs
• Compiles File.cs and creates My.exe: csc /out:My.exe File.cs
• Compiles all of the C# files in the current directory, with optimizations on and defines the DEBUG symbol. The output is File2.exe: csc /define:DEBUG /optimize /out:File2.exe *.cs
• Compiles all of the C# files in the current directory producing a debug version of File2.dll. No logo and no warnings are displayed:
  csc /target:library /out:File2.dll /warn:0 /nologo /debug *.cs
• Compiles all of the C# files in the current directory to Something.xyz (a DLL): csc /target:library /out:Something.xyz *.cs