iOS图片存在本地、再从本地获取图片

//将图片保存到本地
+ (void)SaveImageToLocal:(UIImage*)image Keys:(NSString*)key {
    NSUserDefaults* preferences = [NSUserDefaults standardUserDefaults];
    //[preferences persistentDomainForName:LocalPath];
    [preferences setObject:UIImagePNGRepresentation(image) forKey:key];
}
 
//本地是否有相关图片
+ (BOOL)LocalHaveImage:(NSString*)key {
    NSUserDefaults* preferences = [NSUserDefaults standardUserDefaults];
    //[preferences persistentDomainForName:LocalPath];
    NSData* imageData = [preferences objectForKey:key];
    if (imageData) {
        return YES;
    }
    return NO;
}
 
//从本地获取图片
+ (UIImage*)GetImageFromLocal:(NSString*)key {
    NSUserDefaults* preferences = [NSUserDefaults standardUserDefaults];
    //[preferences persistentDomainForName:LocalPath];
    NSData* imageData = [preferences objectForKey:key];
    UIImage* image;
    if (imageData) {
        image = [UIImage imageWithData:imageData];
    }
    else {
        NSLog(@"未从本地获得图片");
    }
    return image;
}