>Hi,
>
>Here is a segment of code:
>
>

>DataSet ds = new DataSet();
>MyClass.MyMethod( ds );
>
>if (ds =!null)
>{
>    // Error message. Since ds is null.  But why the above ds =! null does not catch it? 
>}
>
>MyClass.MyMethod( DataSet ds)
>{
>     // for testing
>     ds = null;
>}
>

>
>Why does the line ds =! null does not catch that the ds is null?
>
>I also tried to declare the parameter ds as Out but it does not work either.


I'm having trouble with the ds=!null

What are you trying to do? To me that reads if ds = not null do this... it will never hit the error message routine...