iOS-后台返回pdf的NSData，写入pdf

该项目是下载转化后的pdf文件，当请求后发现后台返回的是处理过的psf的NSData文件流，很棘手。

NSData *doubi = responseObject;
//  二进制流写入文件NSString *documentsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)lastObject];//        NSLog(@"documentsDirectory====%@",documentsDirectory);NSFileManager *fileManger = [NSFileManager defaultManager];NSString *testDirectory = [documentsDirectory stringByAppendingString:@"/test"];//        NSLog(@"testDirectory====%@",testDirectory);self.pdfUrl = testDirectory;dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{[self openPdf];});//  创建目录[fileManger createDirectoryAtPath:testDirectory withIntermediateDirectories:YES attributes:nil error:nil];//  创建文件NSString *testPath = [testDirectory stringByAppendingPathComponent:@"text.pdf"];//  写入文件[fileManger createFileAtPath:testPath contents:doubi attributes:nil];

其实是可以直接写入。剩下的就是读出来了。