Given an array of bytes containing the file data, a MIME type, and a file name:

public void DownloadBytes( byte[] bytes, string mimeType, string fileName )
{
  Response.ContentType = mimeType;
  Response.AppendHeader( "Content-Disposition", "attachment;filename=" + fileName );
  Response.BinaryWrite( bytes );
  Response.Flush();
  Response.End();
}

The .NET Framework offers two methods for rounding: Decimal.Round() and Math.Round(). However, both methods implement a type of rounding known as "banker's rounding," which rounds .5 to the nearest even number. This is a different implementation from the "standard" arithmetic rounding most people are familiar with, where .5 rounds "up." Even the definition of "up" can vary, depending on whether the rounding is symmetric or asymmetric. Symmetric rounding rounds in the same direction relative to 0 (either towards or away). Asymmetric rounding always rounds in the same absolute direction (towards positive infinity or negative infinity).

Banker's rounding has its benefits, but it can cause incompatibility with other systems that implement different rounding schemes. For example, Math.Round( 8.5m ) will round to 8 in .NET, but round( 8.5, 2 ) will round to 9 in T-SQL. Inside is source code that implements arithmetic symmetric rounding in .NET, the type of rounding that T-SQL uses.

See How To Implement Custom Rounding Procedures for additional information

/// <summary>
/// Implements alternate rounding methods, in contrast to Decimal.Round()
/// and Math.Round(), which implement banker's rounding (5 rounds to even).
/// See http://support.microsoft.com/?kbid=196652 for other methods.
/// </summary>
public static class Round
{
  #region Methods

  #region ArithSym
  /// <summary>
  /// Rounds using arithmetic (5 rounds up) symmetrical (up is away from zero) rounding
  /// </summary>
  /// <param name="d">A Decimal number to be rounded.</param>
  /// <param name="decimals">The number of significant fractional digits (precision) in the return value.</param>
  /// <returns>The number nearest d with precision equal to decimals. If d is halfway between two numbers, then the nearest whole number away from zero is returned.</returns>
  public static decimal ArithSym( decimal d, int decimals )
  {
    decimal factor = Convert.ToDecimal( Math.Pow( 10, decimals ) );
    int sign = Math.Sign( d );
    return Decimal.Truncate( d * factor + 0.5m * sign ) / factor;
  }
  #endregion ArithSym

  #endregion Methods
}

Here's a mysterious bit of code that doesn't look like it ought to work, but yet it does

select top 1 *
from table
order by newid()

Sometimes you need to comment out blocks of code, but you don't necessarily want to comment out each entire line. As I was performing this very chore today, I thought to myself, "Hey, wouldn't it be nice if there was a keyboard shortcut I could use to comment a selected block of text using comment delimiters?" Then I thought to myself, "I already know how to create macros thanks to Philip's great blogs on macros. Why don't I try writing my own?" So I did. Source code within.

See Philip's great blogs for instructions on how to install macros.

Imports System
Imports EnvDTE
Imports EnvDTE80
Imports System.Diagnostics

Public Module SolutionExplorer

  Sub CollapseNodes()
    ' Get the the Solution Explorer tree
    Dim UIHSolutionExplorer As UIHierarchy
    UIHSolutionExplorer = DTE.Windows.Item( _
     Constants.vsext_wk_SProjectWindow).Object()

    ' Check if there is any open solution
    If (UIHSolutionExplorer.UIHierarchyItems.Count = 0) Then
      Return
    End If

    ' Get the top node (the name of the solution)
    Dim UIHSolutionRootNode As UIHierarchyItem
    UIHSolutionRootNode = UIHSolutionExplorer.UIHierarchyItems.Item(1)

    ' Collapse each project node
    Dim UIHItem As UIHierarchyItem
    For Each UIHItem In UIHSolutionRootNode.UIHierarchyItems
      UIHItem.UIHierarchyItems.Expanded = False
    Next

    ' Select the solution node, or else when you click
    ' on the solution windows scrollbar, it will synchronize the open document
    ' with the tree and pop out the corresponding node which is probably not
    ' what you want.
    UIHSolutionRootNode.Select(vsUISelectionType.vsUISelectionTypeSelect)
  End Sub

  Sub ExpandNodes()
    ' Get the the Solution Explorer tree
    Dim UIHSolutionExplorer As UIHierarchy
    UIHSolutionExplorer = DTE.Windows.Item( _
     Constants.vsext_wk_SProjectWindow).Object()

    ' Check if there is any open solution
    If (UIHSolutionExplorer.UIHierarchyItems.Count = 0) Then
      Return
    End If

    ' Get the top node (the name of the solution)
    Dim UIHSolutionRootNode As UIHierarchyItem
    UIHSolutionRootNode = UIHSolutionExplorer.UIHierarchyItems.Item(1)

    ' Collapse each project node
    Dim UIHItem As UIHierarchyItem
    For Each UIHItem In UIHSolutionRootNode.UIHierarchyItems
      UIHItem.UIHierarchyItems.Expanded = True
    Next

    ' Select the solution node, or else when you click
    ' on the solution windows scrollbar, it will synchronize the open document
    ' with the tree and pop out the corresponding node which is probably not
    ' what you want.
    UIHSolutionRootNode.Select(vsUISelectionType.vsUISelectionTypeSelect)
  End Sub

End Module

My colleague John recently blogged about the unexpected results of using the T-SQL IN operator on a set that contains NULL. Here is another solution to the problem.There are three main ways to test for existence in another table, listed here in order of increasing performance

1. LEFT JOIN and look for NULLs in the right table
2. Use the IN operator
3. Use the EXISTS operator

In general, the EXISTS operator will generate the most efficient query plan, and it also isn't subject to the very NULL pitfall that plagues the IN operator. The query that John posted:

SELECT COUNT(*)
FROM TableTarget
WHERE PrimaryKeyField NOT IN (
  SELECT ForeignKeyField
  FROM TableSource
  WHERE ForeignKeyField IS NOT NULL
)

Could be writtten like this:

SELECT COUNT(*)
FROM TableTarget t
WHERE NOT EXISTS (
  SELECT *
  FROM TableSource
  WHERE ForeignKeyField = t.PrimaryKeyField
)