String to Int in Objective-C

In Objective-C, you can convert a string to an integer using the intValue method. Here's an example:

NSString *numberString = @"42";
NSInteger number = [numberString intValue];
NSLog(@"The number is %ld", (long)number);

In this example, the numberString variable is a string that contains the number "42". The intValue method is used to convert this string to an integer, which is then stored in the number variable. The %ld format specifier is used to print the integer value using NSLog.

Another example could be:

NSString *numberString = @"69";
NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
formatter.numberStyle = NSNumberFormatterDecimalStyle;
NSNumber *myNumber = [formatter numberFromString:numberString];
NSInteger number = [myNumber integerValue];
NSLog(@"The number is %ld", (long)number);

In this example, we also start with a string containing a number ("69" in this case). However, this time we are using the NSNumberFormatter class to convert the string to an NSNumber object. The numberFromString method of the formatter is used to convert the string to NSNumber and then integerValue is used to convert the NSNumber to an NSInteger.