//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//------------------------------------------------------------------------------
namespace System.Web.Util
{
using System.Collections;
using System.Globalization;
//|
///
///
/// For internal use only. This implements a comparison that only
/// checks for equality, so this should only be used in un-sorted data
/// structures like Hashtable and ListDictionary. This is a little faster
/// than using CaseInsensitiveComparer because it does a strict
/// character-by-character equality check rather than a sorted comparison.
///
///
internal class SymbolEqualComparer: IComparer {
//|
///
/// [To be supplied.]
///
internal static readonly IComparer Default = new SymbolEqualComparer();
internal SymbolEqualComparer() {
}
int IComparer.Compare(object keyLeft, object keyRight) {
string sLeft = keyLeft as string;
string sRight = keyRight as string;
if (sLeft == null) {
throw new ArgumentNullException("keyLeft");
}
if (sRight == null) {
throw new ArgumentNullException("keyRight");
}
int lLeft = sLeft.Length;
int lRight = sRight.Length;
if (lLeft != lRight) {
return 1;
}
for (int i = 0; i < lLeft; i++) {
char charLeft = sLeft[i];
char charRight = sRight[i];
if (charLeft == charRight) {
continue;
}
UnicodeCategory catLeft = Char.GetUnicodeCategory(charLeft);
UnicodeCategory catRight = Char.GetUnicodeCategory(charRight);
if (catLeft == UnicodeCategory.UppercaseLetter
&& catRight == UnicodeCategory.LowercaseLetter) {
if (Char.ToLower(charLeft) == charRight) {
continue;
}
}
else if (catRight == UnicodeCategory.UppercaseLetter
&& catLeft == UnicodeCategory.LowercaseLetter){
if (Char.ToLower(charRight) == charLeft) {
continue;
}
}
return 1;
}
return 0;
}
}
}