StreamWriter and Logs

Hi guys.
I need to write logs to text file,so here is my code:

Code (CSharp):

1.  
2. static StreamWriter writer;
3.  
4.     void Start()
5.     {
6.         writer = new StreamWriter(Application.persistentDataPath + Path.DirectorySeparatorChar + "Logs" + Path.DirectorySeparatorChar + "LogFile.txt");
7.     }
8.  
9.     public static void WriteLog(string input)
10.     {
11.         try
12.         {
13.             writer.Write(input + "\n");
14.         }
15.         catch (System.Exception ex)
16.         {
17.             Debug.LogError("ERROR\n" + ex.Message);
18.         }
19.         finally
20.         {
21.             writer.Close();
22.         }
23.     }
24.  

But when i try to call this function from another class via:

Code (CSharp):

1.  
2. DebugLog.WriteLog("Test");
3.  

I see in the console:
NullReferenceException: Object reference not set to an instance of an object
DebugLog.WriteLog (System.String input) (at Assets/Scripts/Debug/DebugLog.cs:21)

 

I'm able to do this in VS 2013,but i can't do this with Unity.What's wrong?

 

is your DebugLog script attached to any gameobject as you create the writer in start method which is not run if its not attached to any object? also if it is then you need to make sure that script run order is correct

half static half monobehaviour classes are not good idea

 

Thanks,but I have already noticed this.
Now it throws:

 

have you created the logs folder there? it will not get autocreated by anything

 

Yes,before I will write something, I check if there is a folder:

Code (CSharp):

1.  
2. static string path = Application.persistentDataPath + Path.DirectorySeparatorChar + "Logs" + Path.DirectorySeparatorChar;
3. if (!Directory.Exists(path))
4. {
5. Directory.CreateDirectory(path);
6. }
7.  

Folder is created, but it still throws an exception:

 

did you actually check with explorer it got created and exists (and code was run)? error is still suggesting its not there

hit Windows+R and paste "C:\Users\Home\AppData\LocalLow\DefaultCompany\New Unity Project\Logs\" with quotes

 

Thanks,I managed to solve it,the problem was actually in other thing