GateKiller

[C#] C# HTML Encoding

2009-03-05T15:08:03-08:00

This is my own attempt at writing a HTML Encoder for ASP.NET.

C&C Welcome :)

public string CleanHtml(object Html) {
	var s = Html.ToString();
	var b = new StringBuilder();
	foreach (char c in s) {
		var l = b.Length;
		
		// Known Replacements
		if (c == '&') {
			b.Append("&amp;");
		}
		if (c == '<') {
			b.Append("&lt;");
		}
		if (c == '>') {
			b.Append("&gt;");
		}
		if (c == '`') {
			b.Append("'");
		}
		
		// Always Encode Extended Ascii Codes
		if ((int)(c) > 127) {
			b.Append("&#" + (int)(c) + ";");
		}
		
		// If nothing was added, add the original char
		if (l == b.Length) {
			b.Append(c);
		}
	}
	return b.ToString();
}

[C#] DirectoryInfo.CopyTo

2008-11-11T17:10:30-08:00

Because the .NET Framework does not contain a function which allows you to copy a directory from one location to another, I thought I would write one:

http://gatekiller.co.uk/Post/DirectoryInfo.CopyTo

Please let me know what you think. Any refactorings to make the code more elegant would be much appreciated.

Cheers
Stephen

public static class DirectoryInfoExtensions
{
    public static void CopyTo(this String Source, String Destination, Boolean Overwrite)
    {
                // Hold directory information
                var SourceDirectory = new DirectoryInfo(Source);
                var DestinationDirectory = new DirectoryInfo(Destination);
                
                // Throw an error is the source directory does not exist
                if (SourceDirectory.Exists == false) {
                        throw new DirectoryNotFoundException();
                }
                
                // Create the destination directory
                if (DestinationDirectory.Exists == false) {
                        DestinationDirectory.Create();
                }
                
                // Loop through the files and copy them
                var SubFiles = SourceDirectory.GetFiles();
                for (int i = 0; i < SubFiles.Length; i++) {
                        var NewFile = Path.Combine(
                                DestinationDirectory.FullName,
                                SubFiles[i].Name
                        );
                        SubFiles[i].CopyTo(NewFile, Overwrite);
                }
                
                // Loop through the directories and call this function
                var SubDirectories = SourceDirectory.GetDirectories();
                for (int i = 0; i < SubDirectories.Length; i++) {
                        var NewDirectory = Path.Combine(
                                DestinationDirectory.FullName,
                                SubDirectories[i].Name
                        );
                        SubDirectories[i].CopyTo(NewDirectory, Overwrite);
                }
        }
}

var SourceDirectory = new DirectoryInfo(@"C:\Users\");
SourceDirectory.CopyTo(@"C:\Users_Backup\", true);

[C#] On Drop all Indexes in SQL Server

2008-10-07T11:55:54-07:00

Rik,

I knew sooner or later someone would ask that question :)

I'm working on producing some complex reports using a 3rd party database. Using the databases current indexes, which I cannot change, the SQL statement takes about 20hours to complete. If copy the database and replace the indexes with my own, it takes about 2 minutes. So I was looking for a quick way to remove the original index quickly so I could insert my own.

[C#] Drop all Indexes in SQL Server

2008-10-07T10:48:07-07:00

The below is some code I recently wrote that attempts to delete all indexes in the current database. It's my first attempt and it's not a very elegant solution so I'm open to suggestions on how I can improve the code.

Thanks

## Transact-SQL [sql]

Declare @Index varchar(128)
Declare @Table varchar(128)

Select
SysIndexes.Name As 'Index',
SysObjects.Name As 'Table'
Into
#Indexes
From
SysIndexes
Inner Join SysObjects On
	SysObjects.id = SysIndexes.id
Where
SysIndexes.Name Is Not Null
and SysObjects.XType = 'U'
Order By
SysIndexes.Name,
SysObjects.Name

While (Select Count(*) From #Indexes) > 0
Begin
	Set @Index = (Select Top 1 [Index] From #Indexes)
	Set @Table = (Select Top 1 [Table] From #Indexes)

	--Print 'Drop Index [' + @Index + '] On [' + @Table + ']' + Char(13)
	Exec ('Drop Index [' + @Index + '] On [' + @Table + ']')
	Delete From #Indexes Where [Index] = @Index and [Table] = @Table
End

Drop Table #Indexes

[C#] On Backup All MS SQL Server Databases

2008-09-22T11:59:22-07:00

@Moodshield: Love it! It's a very simple solution that will suit my server which only has about a dozen databases.

Many Thanks,
Stephen

[C#] Backup All MS SQL Server Databases

2008-09-19T15:19:54-07:00

I've recently blogged about this script and it seems to work very well. Does anyone has any improvements/suggestions or is it nearly perfect?

## SQL Statement [sql]
Use Master

Declare @DatabaseName sysname
Declare @SQLCommand varchar(1024)
Declare curDBName Cursor For
Select [Name] From Master..Sysdatabases
Where [Name] Not In ('tempdb')

Open curDBName
Fetch curDBName Into @DatabaseName

While (@@fetch_status = 0)

Begin
        if databasepropertyex (@DatabaseName,'Status') = 'online'
        Begin
                Select @SQLCommand = 'Backup Database ' + @DatabaseName + 
                ' To Disk = ''D:\Backups\Databases\' + @DatabaseName + '.bak'' With Format'
                execute (@SQLCommand)
        End
        Fetch curDBName Into @DatabaseName
End

Close curDBName
Deallocate curDBName

[C#] On Cache SQL Server Views

2008-07-25T10:50:33-07:00

Just a couple of more changes. Added square brakets around table name and moved the Set @Name to the start of the loop as it was failing on the first table.

## SQL Statement [sql]
Declare @Name varchar(128)
Declare @Table varchar(128)

Select Name Into #Views From SysObjects Where XType = 'V'

While (Select Count(*) From #Views) > 0
Begin
	Set @Name = (Select top 1 Name From #Views)
	Set @Table = 'c' + SubString(@Name, 2, 128)
	If Exists(Select Name From SysObjects Where Name = @Table)
	Begin
		Exec('Drop Table [' + @Table + '] Select * Into [##TempViews] From [' + @Name + '] Select * Into [' + @Table + '] From [##TempViews] Drop Table [##TempViews]')
	End
	Else
	Begin
		Exec('Select * Into [##TempViews] From [' + @Name + '] Select * Into [' + @Table + '] From [##TempViews] Drop Table [##TempViews]')
	End
	
	Delete From #Views Where Name = @Name
End

Drop Table #Views

[C#] On Cache SQL Server Views

2008-07-25T10:20:41-07:00

Jonathan, Thanks very much for that elegant piece of code :) I'm in the process of replacing it with previous code I have.

This was the only addition I made at the end of the statement you provided.

I think from now on, I'll write my Cursor like functionality like you have :)

Cheers
Stephen

## SQL Statement [sql]
Drop Table #Views

[JavaScript] On AJAX makeRequest

2008-07-23T08:35:50-07:00

Does it work if you remove all the try and catch statements?

this.getHttpRequest(identifier).onreadystatechange = function() {
	ajaxChat.handleResponse(identifier);
};

[C#] On Cache SQL Server Views

2008-07-07T11:33:26-07:00

Thanks for the input guys :)

I could update the view based on the last time one of the rows was edited but I think that would decrease the performance of the view in general.

I also can't do indexed views because the views are in a different database to the source tables and this is not allowed in sql server 2005.

I've taken most of the feedback from Mark to make the below which seems a little bit faster :)

Cheers
Stephen

## Statement [sql]
Declare @Name varchar(128)
Declare cCursor Cursor LOCAL FORWARD_ONLY FAST_FORWARD READ_ONLY For Select Name From SysObjects Where XType = 'V'

Open cCursor

Fetch Next From cCursor Into @Name
While @@Fetch_Status = 0
Begin
	Declare @Table varchar(128)
	Set @Table = 'c' + SubString(@Name, 2, 128)
	If Exists(Select Name From SysObjects Where Name = @Table)
	Begin
		Exec('Drop Table ' + @Table + ' Select * Into ##TempViews From ' + @Name + ' Select * Into ' + @Table + ' From ##TempViews Drop Table ##TempViews')
	End
	Else
	Begin
		Exec('Select * Into ##TempViews From ' + @Name + ' Select * Into ' + @Table + ' From ##TempViews Drop Table ##TempViews')
	End
	Fetch Next From cCursor Into @Name
End

Close cCursor
Deallocate cCursor

[C#] Cache SQL Server Views

2008-07-02T15:07:04-07:00

Question: Is there anyway to make this T-SQL statement faster?

Background:
One of our databases has a set of SQL View looking at the main database eg:

vCustomers
vPayments

This transact sql statement ocasionally makes a copy/cache of these views to improve read times in certain area's of the frontend application. (There is also an extra step which creates indexes but this is relatively fast).

The code will then covert the above views into the tables:

cCustomers
cPayments

Of course, the naming convention could be changed to suit your needs.

So is there any way to improve performance?

Many Thanks
Stephen

PS: There wasn't a SQL Language option.

## Statement [sql]
Declare @Name varchar(128)
Declare @Cursor Cursor

Set @Cursor = Cursor For Select Name From SysObjects Where XType = 'V'

Open @Cursor

Fetch Next From @Cursor Into @Name
While @@Fetch_Status = 0
Begin
	Declare @Table varchar(128)
	Set @Table = 'c' + SubString(@Name, 2, 128)
	If Exists(Select Name From SysObjects Where Name = @Table)
	Begin
		Print 'Drop Table ' + @Table
		Exec('Drop Table ' + @Table)
	End
	Exec('Begin Tran Select * Into ' + @Table + ' From ' + @Name + ' Commit')
	Fetch Next From @Cursor Into @Name
End

Close @Cursor
Deallocate @Cursor

[C#] Encryption and Decryption

2008-06-20T14:00:30-07:00

This is my first attempt at Encryption and Decryption functions and I would love your feedback. :)

key and iv are your "passwords" and should be changed.

Many Thanks
Stephen

// ***** Encryption and Decryption ***** //

byte[] Key(string sText) {
	if (Encoding.Default.GetBytes(sText).Length > 32) {
		throw new ArgumentException("Key must be less than 32 bytes long.");
	}
	
	if (Encoding.Default.GetBytes(sText).Length < 1) {
		throw new ArgumentException("Key must be more than 0 bytes long.");
	}
	
	while (Encoding.Default.GetBytes(sText).Length < 32) {
		sText = sText + " ";
	}

	return Encoding.Default.GetBytes(sText);
}

string Encrypt(string sText) {
	// Convert Input Text into Bytes Array
	byte[] bText = Encoding.Default.GetBytes(sText.Trim());
	
	// For storing encrypted bytes
	MemoryStream mStream = new MemoryStream();
	
	// get the algorithm to use
	SymmetricAlgorithm alg = SymmetricAlgorithm.Create("Rijndael");
	
	// Specify Block and Key Size
	alg.BlockSize = 256;
	alg.KeySize = 256;
	
	// Create our own Key and IV
	
	byte[] key = Key("34553513543651433545343545789341");
	byte[] iv = {1,5,6,7,8,1,3,4,5,7,8,9,2,4,5,6,4,5,6,2,4,5,6,4,6,4,2,3,4,8,6,2};
	
	ICryptoTransform encryptor = alg.CreateEncryptor(key, iv); //CreateEncryptor(Byte[] rgbKey, Byte[] rgbIV)
	
	// Tell the crypto stream where and how to encrypt
	CryptoStream crypto = new CryptoStream(mStream, encryptor, CryptoStreamMode.Write);
	
	// Do the actually encryption
	crypto.Write(bText, 0, bText.Length);
	crypto.Close();
	
	// Byte array with encrypted data
	byte[] cipher = mStream.ToArray();
	
	// Return Encrypted Text
	return Convert.ToBase64String(cipher);
}
	
string Decrypt(string sText) {
	// Convert Input Text into Bytes Array
	byte[] bText = Convert.FromBase64String(sText);
	
	// For storing encrypted bytes
	MemoryStream mStream = new MemoryStream(bText);
	
	// get the algorithm to use
	SymmetricAlgorithm alg = SymmetricAlgorithm.Create("Rijndael");
	
	// Specify Block and Key Size
	alg.BlockSize = 256;
	alg.KeySize = 256;
	
	// Create our own Key and IV
	byte[] key = Key("34953913543651433549343595789391");
	byte[] iv = {1,5,6,7,9,1,3,4,5,7,8,9,2,4,9,6,4,5,6,2,4,5,6,4,6,4,2,9,4,8,6,2};

	ICryptoTransform decryptor = alg.CreateDecryptor(key, iv); //CreateDecryptor(Byte[] rgbKey, Byte[] rgbIV)
	
	// Tell the crypto stream where and how to decrypt
	CryptoStream crypto = new CryptoStream(mStream, decryptor, CryptoStreamMode.Read);
	
	// Do the actually decryption
	byte[] bOutput = new byte[bText.Length - 1 + 1];
	crypto.Read(bOutput, 0, bText.Length);
	crypto.Close();
	
	// Return Decrypted Text
	return Encoding.Default.GetString(bOutput).Replace("\x000", String.Empty);
}