CCryptHash::AddString 

Call this method to add a string to the hash.

HRESULT AddString(
   LPCTSTR szData,
   DWORD dwFlags = 0 
) throw( );

Parameters

szData

The string to add.

dwFlags

Set the CRYPT_USERDATA flag to specify that the cryptographic service provider prompts the user to input data directly. In this case, the data is added to the hash, and the application is not allowed to access the data. This flag can be set to allow the user to enter a PIN into the system.