IOS技能点之Foundation之NSString

NSString 一般来说是个常量：__NSCFConstantString

 

根据创建时候的不同，它还有其它类型

NSString *string1 = @"string 1";__NSCFConstantString

NSString *string2 = [NSString stringWithString:@"string 2"];__NSCFConstantString

NSString *string3 = [NSString stringWithFormat:@"string 3"];NSTaggedPointerString

NSString *string4 = [[NSString alloc] initWithString:@"string 4"];__NSCFConstantString

NSString *string5 = [[NSMutableString alloc] initWithString:@"string 5"];__NSCFString

NSString *string6 = string1;__NSCFConstantString