c# - Possible to calculate MD5 (or other) hash with buffered reads? -

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I need to calculate the checksum of large files (gigabytes). It can be completed using the following method Is: 

  private byte [] calcHash (string file) {System.Security.Cryptography.HashAlgorithm ha = System.Security.Cryptography.MD5.Create (); File stream fs = new filestream (file, filemodel open, fileaccess read.); Byte [] hash is =. Compact hash (FS); Fs.Close (); Return hash; }

However, files are usually written in a buffer manner (32MB at a time writes) I am very confident that I saw the override of a hash function Which allows me to write MD5 (or other) hash at the same time, i.e.: calculating the hash of a buffer, feeds the hash resulting in the next strike.

Something like this: (Pseudocode-IIS) 

  byte [] hash = new byte [] {0,0,0,0,0,0,0,0,0 , 0}; While (! Eof) {buffer = readFromSourceFile (); WriteFile (buffer); Hash = calash (buffer, hash); }

What's going to be done by running the ChessShash function on the hash file now?

Now, I can not get any override in this way 3.5 3.5 framework, am I dreaming? Has it ever existed, or am I just lousy in search? The reason for calculating both writing and checksum at one go is that due to the large files it makes sense

< P> You use the TransformBlock and TransformFinalBlock methods to process the data in the chunks. 

  // init MD5 md5 = MD5.Create (); Int offset = 0; // For each block: offset + = md5.TransformBlock (block, 0, block length, block, 0); // For the last block: md5.TransformFinalBlock (block, 0, block.); // Get a byte with code [] hash = MD5. Hash;   
 Note: This works to send all the code to  TransformBlock  (with at least MD5 providers) and then an empty block to  TransformFinalBlock Send to  to finalize the process.

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