How to write if condition in #ifdef. for Staging. in objective-c

In case if you want to negate the condition with 2 build targets, use like this.

#if !(TOWNTALK || EPISD)

Your question is not very clear... If you want multiple conditions in a #ifdef, here is a solution:

#if defined(MYAPP_RELEASE) && defined(MyApp_Staging)
    // ...
#else
    // ...
#endif

In Swift and Xcode 7, the syntax has changed:

#if DEBUG || RELEASE
    let URL = "https://www.example.com/beta"
#elseif APPSTORE
    let URL = "https://www.example.com/prod"
#endif

You could do something like this to contain all the different options including the new Staging Mode and make the whole statement cleaner:

#ifdef MYAPP_PRODUCTION
    buildMode = @"Production";
#elif MYAPP_RELEASE
    buildMode = @"Release";
#elif MYAPP_DEBUG
    buildMode = @"Debug";
#elif MYAPP_STAGING
    buildMode = @"Staging";
#endif