IDebugStackFrame3::InterceptCurrentException
Called by the debugger on the current stack frame when it wants to intercept the current exception.
HRESULT InterceptCurrentException(
INTERCEPT_EXCEPTION_ACTION dwFlags,
UINT64* pqwCookie
);
int InterceptCurrentException(
uint dwFlags,
out ulong pqwCookie
);
Parameters
dwFlags
[in] Specifies different actions. Currently, only the INTERCEPT_EXCEPTION_ACTION value IEA_INTERCEPT is supported and must be specified.pqwCookie
[out] Unique value identifying a particular exception.
Return Value
If successful, returns S_OK; otherwise, returns an error code.
The following are the most common error returns.
Error |
Description |
|---|---|
E_EXCEPTION_CANNOT_BE_INTERCEPTED |
The current exception cannot be intercepted. |
E_EXCEPTION_CANNOT_UNWIND_ABOVE_CALLBACK |
The current execution frame hasn't been searched for a handler yet. |
E_INTERCEPT_CURRENT_EXCEPTION_NOT_SUPPORTED |
This method is not supported for this frame. |
Remarks
When an exception is thrown, the debugger gains control from the run time at key points during the exception handling process. During these key moments, the debugger can ask the current stack frame if the frame wants to intercept the exception. In this way, an intercepted exception is essentially an on-the-fly exception handler for a stack frame, even if that stack frame doesn't have an exception handler (for example, a try/catch block in the program code).
When the debugger wants to know if the exception should be intercepted, it calls this method on the current stack frame object. This method is responsible for handling all details of the exception. If the IDebugStackFrame3 interface is not implemented or the InterceptStackException method returns any error, then the debugger continues processing the exception normally.
Notes
Exceptions can be intercepted only in managed code, that is, when the program being debugged is running under the .NET run time. Of course, third-party language implementers can implement InterceptStackException in their own debug engines if they so choose.
After the interception is complete, an IDebugInterceptExceptionCompleteEvent2 is signaled.