Month: June 2007

WPF

Ink API In WPF

Posted on by sachabarber

I just started to develop a fascination with the Ink API after getting Vista the other day. So I thought about it and decided to create a WPF application which uses Ink to create a very simple paint like application. The finished product looked like this:

main1.png

This app uses the WPF InkCanvas control.

The full article is published here, but just as a taster it can do the following :

* Saving Ink
* Saving Ink as a bitmap
* Loading Ink
* Cut Ink
* Copy Ink
* Paste Ink
* Delete Ink
* Select Ink
* Format Ink
* Stylus Color
* Change stylus type
* Change pen

An example of the some Ink being selected is as follows:

cut.png

I also created another window where you can select the new DrawingAttributes that are applied to the Ink.

stylus.png

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CodeProject, SQL

SQL Server CLR Functions

Posted on by sachabarber

Today we had a requirement to do some pretty strange stuff in SQL which required us to call an encryption library in SQL server. This is something I had not done before, so I thought I would blog about it.

There are several steps involved.

1. Create the CLR Dll for the SQL function to use, and copy it to SQL Binn

2. Register the CLR Dll in SQL server

3. Create a normal SQL function that uses the CLR Dll

The 1st part is straight forward enough, the following code gives an example

 

   1:  using System;
   2:  using System.Collections.Generic;
   3:  using System.Text;
   4:  using Microsoft.SqlServer.Server;
   5:  using System.Data;
   6:  using System.Data.Sql;
   7:  using System.Data.SqlTypes;
   8:  using Encrypt;
   9:  
  10:  public class StoredProcedures
  11:  {
  12:  
  13:      [Microsoft.SqlServer.Server.SqlFunction()]
  14:      public static string Enc(SqlString password, SqlString encStringOut)
  15:      {
  16:          Encryption enc = new Encryption();
  17:          return enc.Encrypt(password.ToString(), encStringOut.ToString());;
  18:      }
  19:  
  20:      [Microsoft.SqlServer.Server.SqlFunction()]
  21:      public static string Dec(SqlString password, SqlString encStringOut)
  22:      {
  23:          Encryption enc = new Encryption();
  24:          return enc.Decrypt(password.ToString(), encStringOut.ToString()); ;
  25:      }
  26:  }

So thats easy enough. Compile this job done.

So next we need to do the SQL server work. So firstly I copied the SQLServerEncryption.Dll to the C:Program FilesMicrosoft SQL ServerMSSQL.1MSSQLBinn directory of the SQL server machine.

I also copied the Dll generated (SQLServerEncryption.Dll) to the C: drive on the SQL server machine, as it makes the Dll registration code that needs to be run for SQL a bit easier.

So we’ve copied to binn and C: so far, so now we need to register the Dll with SQL server. So lets look at that

Firstly we need to allow CLR types in the SQL server installation. Which is either done using the following SQL

 

EXEC dbo.sp_configure 'clr enabled',1 RECONFIGURE WITH

Or if you have issues doing it that way use the SQL Server Surface Area Configuration, use the “Surface Area Configuration For Features” link, and then CLR integration from the presented treeview. Once this is done we can register the CLR Dll with SQL, as follows

 

create assembly SQLServerEncryption from 'c:SQLServerEncryption.dll' WITH PERMISSION_SET = SAFE

Now that weve done that, all thats left to do is create a normal SQL server function that uses the CLR Dll. Which is simply done as follows

 

ALTER FUNCTION [dbo].[ENCRYPT](@password [nvarchar](255), @encStringOut [nvarchar](255))
RETURNS [nvarchar](255) WITH EXECUTE AS CALLER
AS
EXTERNAL NAME [SQLServerEncryption].[StoredProcedures].[Enc]

And that it you can now use the CLR Function as you like. For example

 

dbo.ENCRYPT('xxxx','sb_SQL')
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