Walkthrough: Checking Whether a Hash Value Matches Some Text

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This walkthrough demonstrates how to use the Cryptography Application Block to check whether a previously generated hash matches the hash for some text.

To reproduce the demonstration

  1. Declare the appropriate variables and constants.

    const string hashProvider = "hashprovider";
    byte[] generatedHash;
    
    'Usage
    Const hashProvider As String = "hashprovider"
    Dim generatedHash As Byte()
    
  2. Obtain the text from the user.

    byte[] valueToHash = Encoding.UTF8.GetBytes("password");  
    
    'Usage
    Dim valueToHash As Byte() = Encoding.UTF8.GetBytes("password")
    
  3. Call the static CompareHash method of the Cryptographer class to obtain the hash, supplying the name of the configured hash provider to be used. This code assumes that the member variable generatedHash contains a previously generated hash for some text.

    bool comparisonSucceeded = Cryptographer.CompareHash(hashProvider, valueToHash, generatedHash);
    
    'Usage
    Dim comparisonSucceeded As Boolean = Cryptographer.CompareHash(hashProvider, valueToHash, generatedHash)