转自:http://blog.youkuaiyun.com/u013892686/article/details/49021447
iOS 通过URL获取图片,并保存到本地
NSString *urlString = @"http://1234567890/xxx";
NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:urlString]];
UIImage *image = [UIImage imageWithData:data];
NSString *path = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
NSString *imageFilePath = [path stringByAppendingPathComponent:@"MyImage"];
BOOL success = [UIImageJPEGRepresentation(image, 0.5) writeToFile:imageFilePath atomically:YES];
if (success){
NSLog(@"写入本地成功");
}