text: Objective-C Log Handling
  Advertisements
  NSLog method
  In order to print logs, we use the NSLog method in Objective-C programming language which we have used right from the Hello World example.
  Let us look at a simple code that would print the words "Hello World":
  #import <Foundation/Foundation.h> int main() { NSLog(@"Hello, World! \n"); return 0; }
  Now, when we compile and run the program, we will get the following result.
  2013-09-16 00:32:50.888 demo[16669] Hello, World!
  Disabling logs in Live apps
  Since the NSLogs we use in our application, it will be printed in logs of device and it is not good to print logs in a live build. Hence, we use a type definition for printing logs and we can use them as shown below.
  #import <Foundation/Foundation.h> #if DEBUG == 0 #define DebugLog(...) #elif DEBUG == 1 #define DebugLog(...) NSLog(__VA_ARGS__) #endif int main() { DebugLog(@"Debug log, our custom addition gets \ printed during debug only" ); NSLog(@"NSLog gets printed always" ); return 0; }
  Now, when we compile and run the program in debug mode, we will get the following result.
  2013-09-11 02:47:07.723 demo[618] Debug log, our custom addition gets printed during debug only 2013-09-11 02:47:07.723 demo[618] NSLog gets printed always
  Now, when we compile and run the program in release mode, we will get the following result.
  2013-09-11 02:47:45.248 demo[3158] NSLog gets printed always
  Advertisements