UIImage转换成UIView

#import <QuartzCore/QuartzCore.h>//记住要加上这个头文件！！！

- (UIImage*)convertViewToUIImage:(UIView*)v
{
    UIGraphicsBeginImageContext(v.bounds.size);
    CGContextRef currentContext = UIGraphicsGetCurrentContext();
    [v.layer renderInContext:currentContext];
      // 从当前context中创建一个改变大小后的图片  
    UIImage  *image = UIGraphicsGetImageFromCurrentImageContext();
        // 使当前的context出堆栈  
    UIGraphicsEndImageContext();
    return image;
}

使用方法：

UIView *view =[[UIView alloc]init];

UIImage *image = [self convertViewToUIImage:view];