图片使用

- (void)cutMapView:(UIView *)theView

{

    //************** 得到图片 *******************

    CGRect rect = theView.frame;  //截取图片大小

    //开始取图，参数：截图图片大小

    UIGraphicsBeginImageContext(rect.size);

    //截图层放入上下文中

    [theView.layer renderInContext:UIGraphicsGetCurrentContext()];

    //从上下文中获得图片

    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

    //结束截图

    UIGraphicsEndImageContext();

    //************** 存图片 *******************

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);

    NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.png",@"jietu"]];   // 保存文件的名称

    NSLog(@"filePath = %@",filePath);

    //UIImagePNGRepresentation方法将image对象转为NSData对象

    //写入文件中

    BOOL result = [UIImagePNGRepresentation(image)writeToFile: filePath atomically:YES]; 

    NSLog(@"result = %d",result);

    //*************** 截取小图 ******************

    CGRect rect1 = CGRectMake(90, 0, 82, 82);//创建矩形框

    //对图片进行截取

    UIImage * image2 = [UIImage imageWithCGImage:CGImageCreateWithImageInRect([image CGImage], rect1)]; 

    NSString *filePath2 = [[paths objectAtIndex:0] stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.png",@"jietu2"]];   // 保存文件的名称

    NSLog(@"filePath = %@",filePath);

    BOOL result2 = [UIImagePNGRepresentation(image2)writeToFile:filePath2 atomically:YES];

    NSLog(@"result2 = %d",result2);

    //存入相册

    //UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);

}

图片使用

原文：http://www.cnblogs.com/zhaoxiaolei2015/p/4964355.html