This snippet generates a secure hash string using VB.NET

Have you ever tried to use Color.Blue.ToString and gotten undesired results?
Or have you ever tried to save a color to an INI and not be able to reproduce it the next time around?

The methods below will help you in your conquest of converting the Color structure to HTML (#FF0000) and back to a Color structure again.

This routine will get an image stored in a SQL database (IBM Informix shown here) as a BLOB and return it to the screen.

To place this on an HTML page simply add

I have an MD5 hashed version as well, but can't share that...(So you can have encrypted id's passed)

Have fun,
Jeremy

Is this file the same as that file? The files may or may not be binary. We could compare the modify dates, or the sizes. But, those are not very accurate to know if a file has really changed.

Introducing MD5 Checksum. We can feed the files into Digest::MD5 in binary mode.

This is a great way to do Incremental Backups.

This is also an easy way to verify checksums when downloading files from the internet which list their MD5 Checksums.

You'll need the Digest::MD5 Perl Module.

Generates an 88 character secure hash string for the passed in strings.

Description:
Call one of the overloaded functions and a you will have a randomly generated password.

Generate() - Will generate a password 13 or (more/less) characters in length ranging from A-Z a-z 0-9 and other characters such as @ # %... etc.

Generate(ByVal AsciiMin As Integer, ByVal AsciiMax As Integer)
Generate(ByVal AsciiMin As Char, ByVal AsciiMax As Char) - Allows you to set your ASCII range if you wish not to include number for example.

Generate(ByVal ExcludeValues As String()) - Works like Generate() buts characters passed in the array will not be used to generate the password.

Generate(ByVal AsciiMin As Integer, ByVal AsciiMax As Integer, ByVal ExcludeValues As String())
Generate(ByVal AsciiMin As Char, ByVal AsciiMax As Char, ByVal ExcludeValues As String()) - Works like Generate(ByVal AsciiMin As Integer, ByVal AsciiMax As Integer) & Generate(ByVal AsciiMin As Char, ByVal AsciiMax As Char), but allows you to also exclude characters that you do not wish the generator to use.



UPDATE
03/06/2006: Included use of Phill64's TrueRandom2 class for generating random numbers. Also overloaded the constructor so that a length can be set for the password, if the length is not set the default is set to 13.

The easiest way to give columns in a DataGrid the look you want is to use a DataGridTableStyle and to add a GridColumnStyle for each column in the grid.

From RSA Security's website:
"RC4 is a stream cipher designed by Rivest for RSA Data Security (now RSA Security). It is a variable key-size stream cipher with byte-oriented operations. The algorithm is based on the use of a random permutation. Analysis shows that the period of the cipher is overwhelmingly likely to be greater than 10^100. Eight to sixteen machine operations are required per output byte, and the cipher can be expected to run very quickly in software. Independent analysts have scrutinized the algorithm and it is considered secure."

This implementation encodes the byte stream to be encrypted "in-place".

Example:
Byte[] Key = new Byte[5] { 12, 34, 22, 12, 32 };
Byte[] B = new Byte[10] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
// Examine B array before and after this next call.
RC4(ref B, Key);
// Examine B array before and after this next call.
RC4(ref B, Key);

MySQL 5.x Stored Routines, PHP Session Values, a little CSS oh my! Complex to set up but easy to impliment. Geared toward security, simplicity (of use) and convenience.

This litle snippet shows how to store passwords and then check inputed passwords if they are correct.

(In this snippet we use som pseduo code for the database connection).