CHAPTER 2 BUILDING C# APPLICATIONS
// Use the HelloMessage class!
}
}
HelloMessage h = new HelloMessage();
h.Speak();
You can compile your C# files by listing each input file explicitly.
csc /r:System.Windows.Forms.dll TestApp.cs HelloMsg.cs
As an alternative, the C# compiler allows you to make use of the wildcard character (*) to inform
csc.exe to include all *.cs files contained in the project directory as part of the current build.
csc /r:System.Windows.Forms.dll *.cs
When you run the program again, the output is identical to the previous compiled code. The only
difference between the two applications is the fact that the current logic has been split among multiple
files.
Working with C# Response Files
As you might guess, if you were to build a complex C# application at the command prompt, you would
have to specify a tedious number of input options to inform the compiler how to process your source
code. To help lessen your typing burden, the C# compiler honors the use of response files.
C# response files contain all the instructions to be used during the compilation of your current
build. By convention, these files end in a *.rsp (response) extension. Assume that you have created a
response file named TestApp.rsp that contains the following options (as you can see, comments are
denoted with the # character):
# This is the response file
# for the TestApp.exe example
# of Chapter 2.
# External assembly references.
/r:System.Windows.Forms.dll
# output and files to compile (using wildcard syntax).
/target:exe /out:TestApp.exe *.cs
Now, assuming this file is saved in the same directory as the C# source code files to be compiled,
you are able to build your entire application as follows (note the use of the @ symbol):
csc @TestApp.rsp
If the need should arise, you can also specify multiple *.rsp files as input (e.g., csc @FirstFile.rsp
@SecondFile.rsp @ThirdFile.rsp). If you take this approach, be aware that the compiler processes the
command options as they are encountered. Therefore, command-line arguments in a later *.rsp file can
override options in a previous response file.
Also note that flags listed explicitly on the command line before a response file will be overridden by
the specified *.rsp file. Thus, if you were to enter the following:
csc /out:MyCoolApp.exe @TestApp.rsp
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