思路：将UIImage转换成NSData，然后插入到NSMutableDictionary中，读取时，用NSData读出来，然后再转换成UIImage
－存储
UIImage *image = [self getPicture: id]; NSData *imageData = UIImagePNGRepresentation(image); [tmpDic setObject:imageData forKey:@"imageData"];
－读取
NSData *imageData = [object objectForKey:@"imageData"];
if (imageData) {
UIImage *image = [[UIImage alloc] initWithData:imageData];
imageView.image = image;
}
else{
//...
}