第一種方法

// - (UIImage *)stretchableImageWithLeftCapWidth:(NSInteger)leftCapWidth topCapHeight:(NSInteger)topCapHeight __TVOS_PROHIBITED;

//leftCapWidth:左邊不拉伸區域

//topCapHeight:上面不拉伸區域

UIImage *image =[UIImageimageNamed:@"chatdetail_info_other"];

UIImageView *imageView=[[UIImageViewalloc]initWithFrame

    imageView.image=image;

    [self.viewaddSubview:imageView];

UIImage *image1 =[UIImageimageNamed:@"chatdetail_info_other"];

    image1=[image1 stretchableImageWithLeftCapWidth:image1.size.width*0.3topCapHeight:image1.size.height*0.7];

UIImageView

    imageView1.image=image1;

    [self.viewaddSubview:imageView1];

第二種方法

//- (UIImage *)resizableImageWithCapInsets:(UIEdgeInsets)capInsets NS_AVAILABLE_IOS(5_0);

這個方法只接收一個UIEdgeInsets型別的引數，可以通過設定UIEdgeInsets的left、right、top、bottom來分別指定左端蓋寬度、右端蓋寬度、頂端蓋高度、底端蓋高度

[image1 resizableImageWithCapInsets:UIEdgeInsetsMake(image1.size.height*0.9, image1.size.width*0.9, image1.size.height*0.9, image1.size.width*0.9)];

第三種方法

//- (UIImage *)resizableImageWithCapInsets:(UIEdgeInsets)capInsets resizingMode:(UIImageResizingMode)resizingMode NS_AVAILABLE_IOS(6_0);

//    對比iOS5.0中的方法，只多了一個UIImageResizingMode引數，用來指定拉伸的模式：

//    UIImageResizingModeStretch：拉伸模式，通過拉伸UIEdgeInsets指定的矩形區域來填充圖片

//    UIImageResizingModeTile：平鋪模式，通過重複顯示UIEdgeInsets指定的矩形區域來填充圖片

    [image1 resizableImageWithCapInsets:UIEdgeInsetsMake(image1.size.height*0.9, image1.size.width*0.9, image1.size.height*0.9, image1.size.width*0.9)resizingMode:UIImageResizingModeStretch];