The function returns every MD5 hash every time

Question

I wrote a function that takes the file URL as a parameter and returns the MD5 hash of this file.

The hash generated by this function (in the development environment) corresponds to the hash generated by a third-party tool for the same file.

But when it was deployed in my client QA environment, this function returns different values ​​every time the function is called.

I did some google events and found that the problem might be caused by dev. the server is 64 bits and the QA server is 32 bits. Since I do not have access to my client servers, I deployed it to another 32-bit server and found that the hashes match even on a 32-bit server (does the function work as expected?).

I also considered this question .

here is the function i wrote:

public static String GetMD5HashFromFile(String url) { String response = String.Empty; HttpWebRequest aRequest = (HttpWebRequest)WebRequest.Create(url); using (HttpWebResponse aResponse = (HttpWebResponse)aRequest.GetResponse()) { MD5 md5 = new MD5CryptoServiceProvider(); byte[] retVal = md5.ComputeHash(aResponse.GetResponseStream()); response = "MD5:" + BitConverter.ToString(retVal).Replace("-", string.Empty); } return response; } 

My questions; what can cause this function to return different values? Is there a problem in my function?

Answer 1

Try adding a magazine. So first upload the file to a line (write it somewhere on the disk to compare it later). Then calculate the hash on the disk. I had such a problem in one of my projects, and in this case there were problems with the proxy server, which added something to the answer. But without a file on disk, you cannot compare them.