图片保存与读取

UIImage *bear=[UIImage imageNamed:@"小破熊.png"];

    

    //Document

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

    

    

    /*写入图片*/

    //帮文件起个名

    NSString *uniquePath=[[paths objectAtIndex:0] stringByAppendingPathComponent:@"image.png"];

    NSLog(@"uniquePath is %@",uniquePath);

    //将图片写到Documents文件中

    [UIImagePNGRepresentation(bear)writeToFile: uniquePath    atomically:YES];

    /*读取入图片*/

    //因为拿到的是个路径，所以把它加载成一个data对象

    NSData *data=[NSData dataWithContentsOfFile:uniquePath];

    //直接把该图片读出来

    img3.image=[UIImage imageWithData:data];