Logging-Script doesn't create file

Hey there,

I’m new to Unity and Coding in C# and thus try to learn as much as possible as I go. For a project at uni I have to log the movements of the player in a 3D environment. I tried to modify an already existing C#-script (since I don’t think I’d be able to come up with something like this on my own) but I have encountered a problem: the code runs without a Debug-Error-Message and creates a directory, but afterwards no file is created…
Honestly, I don’t know why. I would greatly appreciate if someone could take a look at this script. Maybe you are able to see something that my “beginner’s eyes” can’t.

Thanks a lot,

using System.IO;
using System;
using System.Collections.Generic;

public class Log : MonoBehaviour 
	public TextWriter fs;
	public GameObject playerobject;
	public Vector3 playerlocation;
	public bool PositionLogging = true;
	bool is_logging = false;
	float deltaTime = 0.1f; // every 100ms
	float timeToLog;

	public void StartLogging () 
		playerobject = GameObject.Find ("RigidBodyFPSController");
		playerlocation = playerobject.transform.position;

		if (is_logging) return;
		if (!Directory.Exists(@".\logs"))
		var nameOfLogFile = (System.DateTime.Now+"")+ "_log.csv";
		this.fs = new StreamWriter(Path.Combine("./logs",nameOfLogFile), true){AutoFlush = true};
		this.fs.WriteLine("#Time is| " + System.DateTime.Now.ToLongTimeString() +" "+  System.DateTime.Now.ToLongDateString() );
		this.fs.WriteLine("#logged object is | " + this.name);
		this.fs.WriteLine("#Format is | time (sec since program start)| name of object logged| x|y|z|");
		is_logging = true;

	void Start () 
		if (!Directory.Exists(@".\logs"))

	void Update() 
		if (!is_logging || Time.time < timeToLog || !PositionLogging) return;
		timeToLog = Time.time + deltaTime;
		fs.Write(String.Format("{0:0.0000000}|", Time.time));
		//foreach(ILoggable l in this.loggables) if(l.Logg()) fs.Write(l.ToLogg());

	private string LoggTransform (GameObject playerobject)
			return String.Format("{1:0.0000}|{2:0.0000}|{3:0.0000}|",

Where do you call StartLogging?