How to check iOS version?

Question

I want to check if the iOS version of the device is greater than 3.1.3 I tried things like:

[[UIDevice currentDevice].systemVersion         


        

Answer 1

As a variation of yasimturks solution, I defined one function and a few enum values instead of five macros. I find it more elegant, but that's a matter of taste.

Usage:

if (systemVersion(LessThan, @"5.0")) ...

.h file:

typedef enum {
  LessThan,
  LessOrEqual,
  Equal,
  GreaterOrEqual,
  GreaterThan,
  NotEqual
} Comparison;

BOOL systemVersion(Comparison test, NSString* version);

.m file:

BOOL systemVersion(Comparison test, NSString* version) {
  NSComparisonResult result = [[[UIDevice currentDevice] systemVersion] compare: version options: NSNumericSearch];
  switch (test) {
    case LessThan:       return result == NSOrderedAscending;
    case LessOrEqual:    return result != NSOrderedDescending;
    case Equal:          return result == NSOrderedSame;
    case GreaterOrEqual: return result != NSOrderedAscending;
    case GreaterThan:    return result == NSOrderedDescending;
    case NotEqual:       return result != NSOrderedSame;
  }
}

You should add your app's prefix to the names, especially to the Comparison type.