Well, maybe...
public class GenericComparer : IComparer {
public GenericComparer( CompareDelegate doCompare ){
if( doCompare == null ){
throw new ArgumentNullException("doCompare");
}
this.doCompare = doCompare;
}
public int Compare( object x, object y ){
if( x == null ){
if( y == null ){
return 0;
}
return -1;
}
if( y == null ){
return 1;
}
return doCompare(x,y);
}
private CompareDelegate doCompare;
}
public delegate int CompareDelegate( object x, object y );
Update:
My colleague Branimir did a little experimentation and found this implementation is similar in performance to a 'regular' methodcall when sorting around 10.000 items. LastComparer.zip (30.65 KB)
See also: A horrible way to calculate a squareroot
using System;
using System.Query;
namespace SquareRoot
{
class Program
{
static void Main(string[] args)
{
int input = 16;
decimal margin = 0.01M;
Func<decimal, decimal> abs = (decimal x) =>
x < 0 ? -x : x;
Func<decimal, bool> goodEnough = (decimal guess) =>
abs(guess * guess - input) < margin;
Func<decimal, decimal> newGuess = (decimal guess) =>
(guess + input / guess) / 2;
Console.WriteLine( "Guess {0}", Try(1, goodEnough, newGuess) );
Console.ReadLine();
}
static decimal Try(decimal guess, Func<decimal, bool> goodEnough, Func<decimal, decimal> newGuess)
{
if (!goodEnough(guess))
{
return Try(newGuess(guess), goodEnough, newGuess);
}
return guess;
}
}
}
But fun to write:
using System;
class MyClass {
public static void Main() {
int input = 16;
decimal margin = 0.01M;
Func<decimal, decimal> abs = delegate(decimal x) {
return x < 0 ? -x : x;
};
Func<decimal, bool> goodEnough = delegate(decimal guess) {
return abs(guess * guess - input) < margin;
};
Func<decimal, decimal> newGuess = delegate(decimal guess) {
return (guess + input / guess) / 2;
};
Console.WriteLine("guess {0}", Try(1, goodEnough, newGuess) );
Console.ReadLine();
}
static decimal Try(decimal guess, Func<decimal, bool> goodEnough, Func<decimal, decimal> newGuess) {
if (!goodEnough(guess)) {
return Try(newGuess(guess), goodEnough, newGuess);
}
return guess;
}
delegate ReturnType Func<U, ReturnType>(U guess);
}
Inspired by Joel and Chris.
Code to create a random validationKey and decryption for use in the machinekey element of the web.config.
Note: valid values for the decryptionKey length are 8 (for DES) or 24 (for 3DES), the resulting key is twice as long and for validationkey 20 to 64.
using System;
using System.Text;
using System.Security.Cryptography;
namespace Crypto {
public class KeyCreator {
public static void Main(String[] args) {
String[] commandLineArgs = System.Environment.GetCommandLineArgs();
string decryptionKey = CreateKey(System.Convert.ToInt32(commandLineArgs[1]));
string validationKey = CreateKey(System.Convert.ToInt32(commandLineArgs[2]));
Console.WriteLine("<machineKey validationKey=\"{0}\" decryptionKey=\"{1}\" validation=\"SHA1\"/>", validationKey, decryptionKey);
}
static String CreateKey(int numBytes) {
RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
byte[] buff = new byte[numBytes];
rng.GetBytes(buff);
return BytesToHexString(buff);
}
static String BytesToHexString(byte[] bytes) {
StringBuilder hexString = new StringBuilder(64);
for (int counter = 0; counter < bytes.Length; counter++) {
hexString.Append( String.Format("{0:X2}", bytes[counter]));
}
return hexString.ToString();
}
}
}
source: mskb312906
The lowest level useful description of the goal of any software is probably best put as "elicit a positive emotional response
in a human".
2005 – DJ Mort
<? xml version="1.0" encoding="utf-8" ?>
< CodeSnippets xmlns="http://schemas.microsoft.com/VisualStudio/2005/CodeSnippet">
< CodeSnippet Format="1.0.0">
< Header>
< Title>sourcesafe header</Title>
< Shortcut>header</Shortcut>
< Description>Code snippet for sourcesafe header.</Description>
< Author>Paul van Brenk</Author>
< SnippetTypes>
< SnippetType>Expansion</SnippetType>
</ SnippetTypes>
</ Header>
< Snippet>
< Declarations>
< Literal />
</ Declarations>
< Code Language="csharp" Kind="file" Delimiter="*">
<![CDATA[ #region SourceSafe header
// $Author: $
// $Modtime: $
// $Workfile: $
// $Revision: 1 $
#endregion
*end* ]]>
</ Code>
</ Snippet>
</ CodeSnippet>
</ CodeSnippets>
File Attachment: sourcesafe_header.zip (550 bytes)
Update: Still haven't found what is causing the exception, but I think the message of the exception is incorrect. For now I'm sticking with the Knuth Shuffle algorithm from the PowerCollections. As suggested by Cyrus.
int[] ints = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 };
System.Random rand = new System.Random((int)DateTime.Now.Ticks);
Array.Sort(ints, delegate(int x, int y){
// since you’re not allowed to return anything else than 0 for x.CompareTo(x)
if
(x == y) {
return 0;
}
return rand.Next(-1,2);
}
);
note: This still throws an exception sometimes, claiming x.CompareTo(x) didn't return 0. I haven't found out why this happens or a pattern when this is happening, but I'll keep looking.
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