Remove leading and trailing whitespace in Objective-C

To remove leading and trailing whitespaces from a string in Objective-C, you can use the NSString method stringByTrimmingCharactersInSet:. Here's an example code snippet:

``objective-c
NSString *myString = @" Hello, world! ";
NSCharacterSet *whitespaceCharacterSet = [NSCharacterSet whitespaceCharacterSet];
NSString *trimmedString = [myString stringByTrimmingCharactersInSet:whitespaceCharacterSet];
NSLog(@"Original string: %@\nTrimmed string: %@", myString, trimmedString);


In this example, we first initialize a string myString containing leading and trailing whitespaces. Then, we create a character set whitespaceCharacterSet that contains all whitespace characters. Finally, we use stringByTrimmingCharactersInSet: to remove any leading or trailing characters that match the whitespaceCharacterSet. The resulting string is stored in trimmedString, which we print to the console along with the original string. The output should be: