internal static int Compare(IComparable o1, IComparable o2, bool caseSensitive)
{
//TODO: turn this "conversion pipeline" into something nicer
try {
if (o1 is string && Numeric.IsNumeric(o2))
{
o1 = (IComparable)Convert.ChangeType(o1, o2.GetType());
}
else if (o2 is string && Numeric.IsNumeric(o1))
{
o2 = (IComparable)Convert.ChangeType(o2, o1.GetType());
}
else if (o1 is string && o2 is Guid)
{
o2 = o2.ToString();
}
else if (o2 is string && o1 is Guid)
{
o1 = o1.ToString();
}
} catch (FormatException) {
throw new EvaluateException(String.Format("Cannot perform compare operation on {0} and {1}.", o1.GetType(), o2.GetType()));
}
if (o1 is string && o2 is string)
{
o1 = ((string)o1).TrimEnd(IgnoredTrailingChars);
o2 = ((string)o2).TrimEnd(IgnoredTrailingChars);
if (!caseSensitive)
{
o1 = ((string)o1).ToLower();
o2 = ((string)o2).ToLower();
}
}
if (o1 is DateTime && o2 is string && Thread.CurrentThread.CurrentCulture != CultureInfo.InvariantCulture)
{
// DateTime is always CultureInfo.InvariantCulture
o2 = (IComparable)DateTime.Parse((string)o2, CultureInfo.InvariantCulture);
}
else if (o2 is DateTime && o1 is string &&
Thread.CurrentThread.CurrentCulture != CultureInfo.InvariantCulture)
{
// DateTime is always CultureInfo.InvariantCulture
o1 = (IComparable)DateTime.Parse((string)o1, CultureInfo.InvariantCulture);
}
else if (o2 is DateTime && o1 is string && Thread.CurrentThread.CurrentCulture != CultureInfo.InvariantCulture)
{
// DateTime is always CultureInfo.InvariantCulture
o1 = (IComparable)DateTime.Parse((string)o1, CultureInfo.InvariantCulture);
}
if (o1.GetType() != o2.GetType())
{
o2 = (IComparable)Convert.ChangeType(o2, o1.GetType());
}
return(o1.CompareTo(o2));
}
private object Unify(object val)
{
if (Numeric.IsNumeric(val))
{
return(Numeric.Unify((IConvertible)val));
}
if (val == null || val == DBNull.Value)
{
return(null);
}
if (val is bool || val is string || val is DateTime || val is Guid || val is char)
{
return(val);
}
if (val is Enum)
{
return((int)val);
}
throw new EvaluateException(String.Format("Cannot handle data type found in column '{0}'.", columnName));
}