NSString *someString = @"   Objective-C Language  \\n";
NSString *trimmedString = [someString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
//Output will be - "Objective-C Language"

Method stringByTrimmingCharactersInSet returns a new string made by removing from both ends of the String characters contained in a given character set.

We can also just remove only whitespace or newline

// Removing only WhiteSpace
NSString *trimmedWhiteSpace = [someString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
//Output will be - "Objective-C Language  \\n"

// Removing only NewLine
NSString *trimmedNewLine = [someString stringByTrimmingCharactersInSet:[NSCharacterSet newlineCharacterSet]];
//Output will be - "   Objective-C Language  "