self.imageview=[[UIImageView alloc] init];

    self.imageview.frame=CGRectMake(100, 100, 100, 100);

    [self.view addSubview:self.imageview];

    self.imageview.layer.borderWidth=2;

    self.imageview.layer.borderColor=[UIColor whiteColor].CGColor;

    self.imageview.layer.masksToBounds=YES;

    self.imageview.layer.cornerRadius=10;

    self.imageview.image=[UIImage imageNamed:@"weibo"];

}

图片圆角属性