Question

think about this:

StreamReader reader = null;

try
{
    reader = new StreamReader(_fileName);
}
catch
{
    //show error that file not found
    reader.Dispose();
    return false;
}

try
{
    //code to read file
}
catch
{
   //show error badly formed file
}
finally
{
    reader.Dispose();
}
//return 

the code above does not work when file can’t be opened because it calls Dispose for null which results in exception.

i don’t want to use using because i want to separate problems with opening the file and reading it. This could be achieved with million different catches but i don’t want to go that way. Plus if using is same as try-finally would “hidden Dispose” throw an unwanted exception anyway? which would be the best way when all i need is to catch an exception opening it and an exception reading it?

Thanks & BR – Matti

Answer 1

It is better to use the using statement:

using(StreamReader reader = new StreamReader(_fileName))
{
}

The compiler will create the correct dispose semantics for you.

And you can still use try with this, not worrying about disposing it yourself:

try
{
    using(StreamReader reader = new StreamReader(_fileName))
    {
         try
         {
            //code to read the file
         }
         catch
         {
            //show error badly formed file
         }
    }
}
catch
{
    // show error that file not found
}