Name
PreserveSigAttribute
Synopsis
When .NET converts a managed method signature to an unmanaged
signature, it changes the return value to a parameter that has
the out
and retval
COM attributes. Instead of the original return value, the
unmanaged method returns a COM HRESULT.
If you want to override
this behavior, attach the
PreserveSigAttribute
to the method.
Something similar happens
when you call unmanaged methods from managed code. In that case,
the [out
, retval]
parameter on the COM side
becomes the return
value, and an HRESULT that indicates an error condition
is translated into a .NET
exception. If you want to be able to access the HRESULT as a
long
return value, use the
PreserveSigAttribute
on the methods in your
COM interface declaration (see
InterfaceTypeAttribute
).
public sealed class PreserveSigAttribute : Attribute { // Public Constructors public method PreserveSigAttribute(); }
Hierarchy
System.Object→System.Attribute→PreserveSigAttribute
Valid On
Method
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