What about using constructs in C #

Question

I see it:

using (StreamWriter sw = new StreamWriter("file.txt"))
{
     // d0 w0rk s0n
}

All I am trying to find does not explain what it does, and instead gives me information about namespaces.

Answer 1

You want to check the documentation for using statement (instead of using using directive, which refers to namespaces).

This basically means that the block is converted to the try/ block finally, and sw.Dispose()is called in the finally block (with a suitable invalidation check).

using , IDisposable - , .

:

• :

  using (Stream input = File.OpenRead("input.txt"),
         output = File.OpenWrite("output.txt"))
  {
      // Stuff
  }
  

• :

  // For some suitable type returning a lock token etc
  using (padlock.Acquire())
  {
      // Stuff
  }
  

• ;

  using (TextReader reader = File.OpenText("input.txt"))
  using (TextWriter writer = File.CreateText("output.txt"))
  {
      // Stuff
  }
  

Answer 2

, . ,

StreamWriter sw = new StreamWriter("file.text");
try {
  // do work 
} finally {
  if ( sw != null ) {
    sw.Dispose();
  }
}

Answer 3

8.13 .

Answer 4

: http://msdn.microsoft.com/en-us/library/yh598w02.aspx

, Dispose IDisposable .

Answer 5

Check Use Instructions