core-bundle/src/Resources/contao/library/Contao/Input.php
public static function postRaw($strKey)
	{
		$strCacheKey = 'postRaw';

		if (!isset(static::$arrCache[$strCacheKey][$strKey]))
		{
			$varValue = static::findPost($strKey);

			if ($varValue === null)
			{
				return $varValue;
			}

			$varValue = static::preserveBasicEntities($varValue);
			$varValue = static::xssClean($varValue);

			if (!\defined('TL_MODE') || TL_MODE != 'BE')
			{
				$varValue = static::encodeInsertTags($varValue);
			}

			static::$arrCache[$strCacheKey][$strKey] = $varValue;
		}

		return static::$arrCache[$strCacheKey][$strKey];
	}
public static function postRaw($strKey)
	{
		$strCacheKey = 'postRaw';

		if (!isset(static::$arrCache[$strCacheKey][$strKey]))
		{
			$varValue = static::findPost($strKey);

			if ($varValue === null)
			{
				return $varValue;
			}

			$varValue = static::preserveBasicEntities($varValue);
			$varValue = static::xssClean($varValue);

			if (!\defined('TL_MODE') || TL_MODE != 'BE')
			{
				$varValue = static::encodeInsertTags($varValue);
			}

			static::$arrCache[$strCacheKey][$strKey] = $varValue;
		}

		return static::$arrCache[$strCacheKey][$strKey];
	}
Return a raw, unsafe $_POST variable

@param string $strKey The variable name

@return mixed The raw variable value