CCNetConfig

Since it is Halloween, I thought I would use a class today from System.Security.Cryptography namespace. This little class shows how you can create an MD5 hash for a stream

 1using System;
 2using System.Security.Cryptography;
 3using System.Net;
 4
 5namespace ALittleClass ...{
 6  class Program ...{
 7    static void Main ( string[ ] args ) ...{
 8      // create the md5 provider
 9      MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider ( );
10      // you can hash any array of bytes or a stream...
11      // for this example, i will get google.com and hash the response stream
12      WebRequest req = WebRequest.Create( "http://google.com/" );
13      Console.WriteLine ( "Retrieving {0}", req.RequestUri.ToString ( ) );
14      // get the response
15      WebResponse resp = req.GetResponse(  );
16      Console.WriteLine ( "Computing the hash..." );
17      // hash the stream
18      byte[] hash = md5.ComputeHash ( resp.GetResponseStream ( ) );
19      // base64 encode the hash
20      string b64 = Convert.ToBase64String ( hash );
21      Console.WriteLine ( "Google Hash: {0}", b64 );
22      Console.ReadLine ( );
23    }
24  }
25}

Output

Retrieving http://google.com/
Computing the hash...
Google Hash: /PX2eXxl/jvS/7bNW1sP+g==

There are a few people that want support for Xml Entities in CCNetConfig to reference external files and values. While I am still trying to make that work, but it doesn't look like it will soon, I need some feedback on a new feature I plan on implementing. It is in the line of supporting the entities. What I am thinking is adding the ability to create entities in the UI and use those entities as values for properties. The entities would be at the configuration level and would be used in properties for projects and sub-properties. I still have to see how the current serializer/deserializer will act with these because with entities that reference external files, they are 'brought in' to the main document. If this doesn't happen for simple values like the name of the source control server then is this a feature that you would like see implemented?

Since I missed a couple posts for "A Little Class", I am posting another one this week, System.Security.SecureString

A SecureString represents a string that should be kept confidential when used and removed from memory when no longer needed. An instance of the System.String class is both immutable and can not be scheduled for garbage collection when no longer needed. if using a String object to store sensitive information such as a password or credit card number, there is risk that the information can be revealed later because your application can not delete the data from computer memory.

A SecureString is similar to a String in that it contains a string value. However,  a SecureString is encrypted when initialized or when modified. It can be modified until your application marks it readonly and can be removed from memory by your application or by the Garbage Collector.

 1using System;
 2using System.Security;
 3using System.Runtime.InteropServices;
 4
 5namespace ALittleClass ...{
 6  class Program ...{
 7    static void Main ( string[] args ) ...{
 8      // create the secure string
 9      SecureString password = new SecureString ( );
10      // prompt for the password
11      Console.Write ( "Enter Password:" );
12      // read the keys pressed by the user
13      ConsoleKeyInfo nextKey = Console.ReadKey(true);
14      // read the password entered from standard input.
15      while ( nextKey.Key != ConsoleKey.Enter ) ...{
16        // check if the user is backspacing to make a correction...
17        if ( nextKey.Key == ConsoleKey.Backspace && password.Length > 0 ) ...{
18          // remove the character from the secure string
19          password.RemoveAt ( password.Length - 1 );
20          // erase the character on the console.
21          Console.Write ( nextKey.KeyChar );
22          Console.Write ( " " );
23          Console.Write ( nextKey.KeyChar );
24        } else ...{
25          // add the character to the secure string
26          password.AppendChar ( nextKey.KeyChar );
27          // display a character in the console
28          Console.Write ( "*" );
29        }
30        nextKey = Console.ReadKey ( true );
31      }
32      Console.WriteLine ( );
33
34      // lock the password down so it can not be changed further
35      password.MakeReadOnly ( );
36
37      // so we can read the value we need to do some conversion...
38      IntPtr bstr = Marshal.SecureStringToBSTR ( password );
39      string encPassword = Marshal.PtrToStringAuto(bstr);
40      // destroy the password and remove from memory.
41      password.Dispose ( );
42
43      Console.WriteLine ( "Secure password: {0}", encPassword );
44      Console.WriteLine ( "Press Enter To Continue..." );
45      Console.ReadLine ( );
46    }
47  }
48}

Enter Password:********************
Secure password: i entered a password
Press Enter To Continue...

This weeks Little Class is the System.IO.Path. This is a very useful class that allows generate a temp file name, combine paths together, get just the extension of a file and more. The code below shows all the available methods and public accessible fields of the System.IO.Path class. This class only has static members.

 1using System;
 2using System.Collections.Generic;
 3using System.Text;
 4using System.IO;
 5
 6namespace ALittleClass ...{
 7  class Program ...{
 8    static void Main ( string[ ] args ) ...{
 9      // get a file
10      FileInfo file = new FileInfo ( typeof ( Program ).Assembly.Location );
11      // output the full file name
12      Console.WriteLine ( file.FullName );
13      // changes the extension of the file and returns the new filename
14      Console.WriteLine ( Path.ChangeExtension ( file.FullName, "txt" ) );
15      // combines 2 paths together
16      Console.WriteLine ( Path.Combine ( file.Directory.FullName, "myFile.txt" ) );
17      // gets only the directory name
18      Console.WriteLine ( Path.GetDirectoryName ( file.FullName ) );
19      // gets only the file extension (includes the dot)
20      Console.WriteLine ( Path.GetExtension ( file.FullName ) );
21      // gets only the file name (with the extension)
22      Console.WriteLine ( Path.GetFileName ( file.FullName ) );
23      // gets only the file name with out the extension and the dot
24      Console.WriteLine ( Path.GetFileNameWithoutExtension ( file.FullName ) );
25      // gets the full path of a file name
26      Console.WriteLine ( Path.GetFullPath ( file.Name ) );
27      // gets an array of characters that are invalid in a file name
28      Console.WriteLine ( new string ( Path.GetInvalidFileNameChars ( ) ) );
29      // gets an array of characters that are invalid in a path
30      Console.WriteLine ( new string ( Path.GetInvalidPathChars ( ) ) );
31      // Gets the root path of a path
32      Console.WriteLine ( Path.GetPathRoot ( file.FullName ) );
33      // gets a random file name
34      Console.WriteLine ( Path.GetRandomFileName ( ) );
35      // gets a temp file name
36      Console.WriteLine ( Path.GetTempFileName ( ) );
37      // gets the temp path
38      Console.WriteLine ( Path.GetTempPath ( ) );
39      // checks if a file has an extension
40      Console.WriteLine ( Path.HasExtension ( file.FullName ) );
41      // checks if a path is rooted
42      Console.WriteLine ( Path.IsPathRooted ( file.FullName ) );
43      // gets the character that separates directories
44      Console.WriteLine ( Path.DirectorySeparatorChar );
45      // gets the alternate character that can be used to separate directories
46      Console.WriteLine ( Path.AltDirectorySeparatorChar );
47      // gets the character used to separate multiple paths
48      Console.WriteLine ( Path.PathSeparator );
49      // gets the character used to separate the volume from the path
50      Console.WriteLine ( Path.VolumeSeparatorChar );
51      Console.ReadLine ( );
52    }
53  }
54}
55
56

H:\dotNetProjects\ALittleClass\ALittleClass\bin\Debug\ALittleClass.exe
H:\dotNetProjects\ALittleClass\ALittleClass\bin\Debug\ALittleClass.txt
H:\dotNetProjects\ALittleClass\ALittleClass\bin\Debug\myFile.txt
H:\dotNetProjects\ALittleClass\ALittleClass\bin\Debug
.exe
ALittleClass.exe
ALittleClass
H:\dotNetProjects\ALittleClass\ALittleClass\bin\Debug\ALittleClass.exe
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Doppler, my favorite podcast download client just announced that it will be an open source project hosted on CodePlex. They have not yet published the source or activated the project but plan to do so shortly. The license has not been decided as of now either. I am glad this is going open source because I really love this client but have problems with it crashing from time to time.