public static bool IsEquivalent(this string s1, string s2, StringEquivalenceOptions options)
{
int idx1 = 0, idx2 = 0;
if (string.Equals(s1, s2))
{
return(true);
}
if (string.IsNullOrWhiteSpace(s1) || string.IsNullOrWhiteSpace(s2))
{
return(false);
}
if (options.HasFlag(StringEquivalenceOptions.IgnoreLeadingSpaces))
{
SkipToNextNonSpace(s1, ref idx1);
SkipToNextNonSpace(s2, ref idx2);
}
var caseInsensitive = options.HasFlag(StringEquivalenceOptions.CaseInsensitive);
while (idx1 < s1.Length && idx2 < s2.Length)
{
if (options.HasFlag(StringEquivalenceOptions.MultipleSpacesAreEquivalent))
{
var ws1 = JumpOverWhiteSpace(s1, ref idx1);
var ws2 = JumpOverWhiteSpace(s2, ref idx2);
if (ws1 ^ ws2)
{
return(false);
}
}
if (!((caseInsensitive || s1[idx1] == s2[idx2]) && (!caseInsensitive || char.ToUpperInvariant(s1[idx1]) == char.ToUpperInvariant(s2[idx2]))))
{
return(false);
}
idx1++;
idx2++;
}
if (!options.HasFlag(StringEquivalenceOptions.IgnoreTrailingSpaces))
{
return(idx1 == s1.Length && idx2 == s2.Length);
}
SkipToNextNonSpace(s1, ref idx1);
SkipToNextNonSpace(s2, ref idx2);
return(idx1 == s1.Length && idx2 == s2.Length);
}