Unhandled exception in foreach (object obj in list)

[Emily]

Hi,

I have the following code and an unhandled exception.

Code:

UnitInventory inventory;
foreach (object obj in list) //debugger points to list where
exception occurs
{
inventory = (UnitInventory)obj;
Console.WriteLine(inventory);
}

Error message:

"An unhandled exception of type 'System.InvalidOperationException'
occurred in mscorlib.dll

Additional information: Specified IComparer threw an exception."

Any suggestion on how to get rid of the error? Thanks!

 

[Jon Skeet [C# MVP]]

Hi,

I have the following code and an unhandled exception.

Code:

UnitInventory inventory;
foreach (object obj in list) //debugger points to list where
exception occurs
{
inventory = (UnitInventory)obj;
Console.WriteLine(inventory);
}

Error message:

"An unhandled exception of type 'System.InvalidOperationException'
occurred in mscorlib.dll

Additional information: Specified IComparer threw an exception."

Any suggestion on how to get rid of the error? Thanks!

Could you post a short but complete program which demonstrates the
problem?

See http://www.pobox.com/~skeet/csharp/complete.html for details of
what I mean by that.

 

[John A. Bailo]

Can every obj in list be cast as Type UnitInventory?

 

[Helge Jensen]

Hi,

I have the following code and an unhandled exception.

Code:

UnitInventory inventory;
foreach (object obj in list) //debugger points to list where
exception occurs

"An unhandled exception of type 'System.InvalidOperationException'
occurred in mscorlib.dll

Additional information: Specified IComparer threw an exception."

Any suggestion on how to get rid of the error? Thanks!

The lists GetEnumerator(), or the returned IEnumerator's MoveNext() or
Current, is throwing InvalidOperationException.

To make debugging easier, rewrite the loop as:

IEnumerator it = list.GetEnumerator();
while ( it.MoveNext(); ) {
object obj = it.Current;
// stuff
}

which will allow you to step through what's happening in the foreach.