新人请教OC中self用法

Question

新人小白，求教下面的获取文本框、标签的文本属性为什么都要用self.num1.text，self.resultLabel.text， 不能直接用num1.text，resultLabel.text？？？

#import "HMViewController.h"

@interface HMViewController ()
@property (nonatomic, weak) IBOutlet UITextField *num1;
@property (nonatomic, weak) IBOutlet UITextField *num2;
@property (nonatomic, weak) IBOutlet UILabel *resultLabel;

@end

@implementation HMViewController

• (IBAction)compute
  {
  NSString *num1 = self.num1.text;
  NSString *num2 = self.num2.text;

  int result = num1.intValue + num2.intValue;

  self.resultLabel.text = [NSString stringWithFormat:@"%d", result];

  [self.view endEditing:YES];
  }

@end

Answer 1

http://blog.csdn.net/hahahacff/article/details/39586451