// Aufrufen
String GetVar = getStringPartByNr(packetBuffer, ',', 1);

// Funktion
	String getStringPartByNr(const String &data, char separator, int index)
	{
		// -----------------------------------------
		// --Split String mit Seperator und index---
		// -----------------------------------------

		int found = 0;
		int strIndex[] = {0, -1};
		int maxIndex = data.length() - 1;

		for (int i = 0; i <= maxIndex && found <= index; i++)
		{
			if (data.charAt(i) == separator || i == maxIndex)
			{
				found++;
				strIndex[0] = strIndex[1] + 1;
				strIndex[1] = (i == maxIndex) ? i + 1 : i;
			}
		}
		return found > index ? data.substring(strIndex[0], strIndex[1]) : "";
	}