I need save huge data in a file in byte format.Sometimes i have to insert some bytes in a special position.I use FileStream,but i can only append byte at the end of the file or rewrite data in the file.So how can i insert bytes into the file without destroy other data?
thanks
4  1294 
I would say read the whole file.
Write it back to the file until you reach your "special position"
Write your "special data"
and write back all the rest of the file that is left
I would say read the whole file.
Write it back to the file until you reach your "special position"
Write your "special data"
and write back all the rest of the file that is left
thanks ,do you mean that i should move the rest of the file to another file and then move back?
My file is big,Maybe 200M~2000M.I think it will be slow to move so many data.
In that case, you may want to read the file upto the point where you want to start writing.
Copy all the data from there onwards, write your new data, and write the copied data.
If you want to reduce that (maybe because you might want to inser your data early in the file => worst case, right at the begining)
you may want to read the file in chunks.
So if your new data is 10bytes.
read the first 10 bytes, write your 10 bytes.
Read the next 10 bytes, write the next 10 bytes, and so on.
obviously you can increase this size for a faster response,
Cheers
In that case, you may want to read the file upto the point where you want to start writing.
Copy all the data from there onwards, write your new data, and write the copied data.
If you want to reduce that (maybe because you might want to inser your data early in the file => worst case, right at the begining)
you may want to read the file in chunks.
So if your new data is 10bytes.
read the first 10 bytes, write your 10 bytes.
Read the next 10 bytes, write the next 10 bytes, and so on.
obviously you can increase this size for a faster response,
Cheers
Good idea,Thank you very much!
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