Check iOS version at runtime?

Question

This is sort of a follow on from my last question. I am using beginAnimations:context: to setup an animation block to animate some UITextLabels. However I notic

Answer 1

to conform to version specified in system defines

//#define __IPHONE_2_0 20000
//#define __IPHONE_2_1 20100
//#define __IPHONE_2_2 20200
//#define __IPHONE_3_0 30000
//#define __IPHONE_3_1 30100
//#define __IPHONE_3_2 30200
//#define __IPHONE_4_0 40000
You can write function like this ( you should probably store this version somewhere rather than calculate it each time ):

+ (NSInteger) getSystemVersionAsAnInteger{
    int index = 0;
    NSInteger version = 0;

    NSArray* digits = [[UIDevice currentDevice].systemVersion componentsSeparatedByString:@"."];
    NSEnumerator* enumer = [digits objectEnumerator];
    NSString* number;
    while (number = [enumer nextObject]) {
        if (index>2) {
            break;
        }
        NSInteger multipler = powf(100, 2-index);
        version += [number intValue]*multipler;
        index++;
    }
return version;
}

Then you can use this as follows:

if([Toolbox getSystemVersionAsAnInteger] >= __IPHONE_4_0)
{
  //blocks
} else 
{
  //oldstyle
}