CDav::GetFilterOperation

static function GetFilterOperation($key)
{
	$strNegative = "N";
	if (mb_substr($key, 0, 1) == "!")
	{
		$key = mb_substr($key, 1);
		$strNegative = "Y";
	}

	$strOrNull = "N";
	if (mb_substr($key, 0, 1) == "+")
	{
		$key = mb_substr($key, 1);
		$strOrNull = "Y";
	}

	if (mb_substr($key, 0, 2) == ">=")
	{
		$key = mb_substr($key, 2);
		$strOperation = ">=";
	}
	elseif (mb_substr($key, 0, 1) == ">")
	{
		$key = mb_substr($key, 1);
		$strOperation = ">";
	}
	elseif (mb_substr($key, 0, 2) == "<=")
	{
		$key = mb_substr($key, 2);
		$strOperation = "<=";
	}
	elseif (mb_substr($key, 0, 1) == "<")
	{
		$key = mb_substr($key, 1);
		$strOperation = "<";
	}
	elseif (mb_substr($key, 0, 1) == "@")
	{
		$key = mb_substr($key, 1);
		$strOperation = "IN";
	}
	elseif (mb_substr($key, 0, 1) == "~")
	{
		$key = mb_substr($key, 1);
		$strOperation = "LIKE";
	}
	elseif (mb_substr($key, 0, 1) == "%")
	{
		$key = mb_substr($key, 1);
		$strOperation = "QUERY";
	}
	else
	{
		$strOperation = "=";
	}

	return array("FIELD" => $key, "NEGATIVE" => $strNegative, "OPERATION" => $strOperation, "OR_NULL" => $strOrNull);
}