Setting an instance to null

Marc

I have a decrypter that returns a decrypted value and decrypted catagory. If for some reason my program cannot find the catagory is it best to set the instance of the catagory to null or dispose it? This way I can still provide the decrypted value, but not the decrypted catagory. Below is what I have done thus far.....

GetKey key = GetKey.Instace[category.ToLower()];

bool ctgry = key.DoesCategoryExist(category.ToLower());

if (ctgry == false)

{

//key.dispose();

key = null; // which should work best?

}

I am also trying to log the fact that no category exists within the if statement or upon the diposel of key without throwing an exemption.

2 Replies

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Vulpes12y ago
Accepted answer
Well, you can only call Dispose() if your GetKey class implements the IDisposable interface and it's only likely to do that if it needs some kind of 'unmanaged' resource (such as a file handle or database connection) to do its work.

Note that calling Dispose() doesn't actually force the object to be garbage collected. It will only be garbage collected when there are no longer any references to it. Setting the reference to null will therefore accelerate this.

So, if the category can't be found and GetKey does implement IDisposable, I'd do both:

GetKey key = GetKey.Instace[category.ToLower()];

bool ctgry = key.DoesCategoryExist(category.ToLower());
if (ctgry == false)
{
key.Dispose();
key = null;
WriteToLog("A category named {0} doesn't exist", category);
}

If it doesn't implement IDisposable, just set key to null.

As far as logging is concerned, I'd just write a method which logs the appropriate message to a file. For example:

static void WriteToLog(string message)
{
string[] lines = new string[3];
lines[0] = DateTime.Now.ToString();
lines[1] = message;
lines[2] = "";
System.IO.File.AppendAllLines("error.log", lines);
}
Marc12y ago
Thanks for the in depth explanation Vulpes!