C#

DaveyM69 wrote:

Ah, I hadn't reread the P/Invoke one

Al Beback wrote:

that article doesn't address my specific example where a variable is not explicitly declared inside the using statement.

public static void Main(string[] args)
{
    using (new SomeIDisposableClass())
    {
        Console.WriteLine("Hello World!");
    }
    Console.ReadKey(true);
}

.method public hidebysig static 
  void Main(string[] args) cil managed
{
    .entrypoint
    .maxstack 2
    .locals init (
        [0] class using_test.SomeIDisposableClass CS$3$0000,
        [1] bool CS$4$0001)
    L_0000: nop 
    L_0001: newobj instance void 
              using_test.SomeIDisposableClass::.ctor()
    L_0006: stloc.0 
    L_0007: nop 
    L_0008: ldstr "Hello World!"
    L_000d: call void [mscorlib]System.Console::WriteLine(string)
    L_0012: nop 
    L_0013: nop 
    L_0014: leave.s L_0026
    L_0016: ldloc.0 
    L_0017: ldnull 
    L_0018: ceq 
    L_001a: stloc.1 
    L_001b: ldloc.1 
    L_001c: brtrue.s L_0025
    L_001e: ldloc.0 
    L_001f: callvirt instance void 
              [mscorlib]System.IDisposable::Dispose()
    L_0024: nop 
    L_0025: endfinally 
    L_0026: nop 
    L_0027: ldc.i4.1 
    L_0028: call valuetype 
              [mscorlib]System.ConsoleKeyInfo 
              [mscorlib]System.Console::ReadKey(bool)
    L_002d: pop 
    L_002e: ret 
    .try L_0007 to L_0016 finally handler L_0016 to L_0026
}

I are Troll

IDisposable disposable = null;
try
{
 disposable =  new SomeIDisposableClass()
 SomeCode();
}
finally
{
 disposable.Dispose();
}

d@nish wrote:

Why and when would you write a code like that?

d@nish wrote:

Why and when would you write a code like that?

I are Troll

public class AppCursor : IDisposable
    {

        Cursor _currentCursor = null;
        bool _setDefault;

        public AppCursor(Cursor cursor, bool setDefault)
        {
            _currentCursor = Cursor.Current;
            _setDefault = setDefault;
            Cursor.Current = cursor;
        }

        #region IDisposable Members

        public void Dispose()
        {
            Cursor.Current = (_setDefault) ? Cursors.Default : _currentCursor;
            
            // Even with disposing the cursor object, form works but am not sure whether it should be there or not.
            _currentCursor.Dispose();
            _currentCursor = null;
        }

        #endregion
    }

d@nish wrote:

As far as its equivalent is concerned, just see the IL through ILDAsm or reflector and it would make things a bit clear.

    SomeIDisposableClass CS$3$0000;
    bool CS$4$0001;
    CS$3$0000 = new SomeIDisposableClass();
Label_0007:
    try
    {
        SomeCode();
        goto Label_0021;
    }
    finally
    {
    Label_0011:
        CS$4$0001 = CS$3$0000 == null;
        if (CS$4$0001)
        {
            goto Label_0020;
        }
        CS$3$0000.Dispose();
    Label_0020:;
    }
Label_0021:;

    SomeIDisposableClass CS$3$0000;
    CS$3$0000 = new SomeIDisposableClass();
Label_0006:
    try
    {
        SomeCode();
        goto Label_0017;
    }
    finally
    {
    Label_000D:
        if (CS$3$0000 == null)
        {
            goto Label_0016;
        }
        CS$3$0000.Dispose();
    Label_0016:;
    }
Label_0017:

harold aptroot wrote:

Wow, everyone got it wrong Debug or Release?The debug code (bugs in Reflector corrected by looking at the MSIL)

I are Troll

L_0011: ldloc.0
L_0012: ldnull
L_0013: ceq
L_0015: stloc.1
L_0016: ldloc.1
L_0017: brtrue.s L_0020