Read Binary File

Question

hello this is an expert topic and winner have expert answer. I have a Binary File and save multiple files in this Binary file. this file is QuickBasic BSAVE binary data please help me Experts Regards Thanks

ehsan · Answer

Hi Thanks For Your response Johnny GC . I Found 0xFD result for valid bsave file header but I can't extract the ((( Files ))) into this file in C# this is first lines in hex editor .........................lq........8...mOC20.......>.OMEGA FS........@........-...F__3USER FAT12@.@T!.....U.......@.... ` please help me more Thanks Advance Regards

Johnny GC · Answer

hi I do not know this type of format but I`ve worked a lot with binary files not only in c# so this is your header info googled: The total length of the header is 7 bytes: Byte 1 IdByte This must evaluate to &HFD to be a valid BSAVE file. In QuickBasic use ASC function of a 1 character string variable. Byte 2-3 Segment Byte 4-5 Address Byte 6-7 Length Useful if you wish to dimension an array ahead of time to hold the BLOAD. so it seems you need to open file stream and do a repetitive read this read will consist in: 1. first 7 bytes to know what data and size you have 2. the next X bytes where X is the Length (bytes 6+7 from header) note that the length of the data may be bytes 6+7 from header or bytes 6+7 from header MINUS 7 cause 7 is header`s length for example lets say you have this 7 bytes in the beginning: 0x01 0x02 0x03 0x04 0x05 0x06 0x07 you have a segment identified with 0x0203 an address of 0x0405 and a length of 0x0607 which is 1543 in decimal thus you need to read then 1543 or 1543-7 bytes (if the length includes header) OPEN FILE POSITION BEGINNING LOOP READ 7 CHECK LENGTH READ LENGTH || LENGTH-7 ENDLOOP hope this helps