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=[[pathsobjectAtIndex: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=[NSDatadataWithContentsOfFile:uniquePath];

    //直接把该图片读出来

    img3.image=[UIImageimageWithData:data];