NSData 转 bytes 字节数据

NSData *data = [NSData dataWithContentsOfFile:filePath];NSUInteger len = [data length];Byte *byteData = (Byte*)malloc(len);memcpy(byteData, [data bytes], len);

NSString *strPath = @"/Users/user/Desktop/jkk.txt";    NSLog(@"string = %@",[[NSString alloc]initWithContentsOfFile:strPath encoding:NSUTF8StringEncoding error:Nil]);    NSData *strData = [[NSData alloc]initWithContentsOfFile:strPath];    NSLog(@"size = %d字节; strData = %@",strData.length,strData.description);        NSUInteger len = [strData length];    Byte *byteData = (Byte*)malloc(len);    memcpy(byteData, [strData bytes], len);        for (int i = 0; i < len; i++) {        printf("%c",byteData[i]);    }            NSData *Data222 = [[NSData alloc]initWithBytes:byteData length:len];    NSLog(@"Data222 : %@",Data222);        NSRange rangeData = {
   0,3};    NSData *subData = [strData subdataWithRange:rangeData];    NSLog(@"subData : %@",subData);        NSData *Data333 = [[NSData alloc]initWithData:subData];    NSLog(@"Data333: %@",[[NSString alloc]initWithData:Data333 encoding:NSUTF8StringEncoding]);

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