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Method overview
nsrefcnt AddRef();Violates the XPCOM interface guidelines |
void QueryInterface(in nsIIDRef uuid, [iid_is(uuid),retval] out nsQIResult result); |
nsrefcnt Release();Violates the XPCOM interface guidelines |
Methods
AddRef()
Notifies the object that an interface pointer has been duplicated.
nsrefcnt AddRef();
Parameters
None.
Return value
An integer value that is generally ignored.
QueryInterface()
The QueryInterface method provides runtime type discovery.
Note: The interface pointer, aResult, returned by QueryInterface must be released by a call to Release() when it is no longer needed. QueryInterface is a symmetric, transitive, and reflexive operator.
void QueryInterface( in nsIIDRef uuid, [iid_is(uuid),retval] out nsQIResult result );
Parameters
-
uuid -
The
uuidof the requested interface -
result - The resulting interface pointer.
Exceptions thrown
-
NS_ERROR_NO_INTERFACE - The requested interface is not available.
Release()
Notifies the object that an interface pointer has been destroyed and any resources the object held on behalf of the client can be released.
nsrefcnt Release();
Parameters
None.
Return value
An integer value that is generally ignored.
Remarks
The method descriptions above were taken from Essential COM by Don Box. The point of those descriptions is to highlight the fact that AddRef() and Release() do not necessarily correspond to incrementing and decrementing a counter, respectively, even though that is how they are usually implemented.
On Win32 systems, nsISupports is ABI-compatible with Microsoft COM's IUnknown interface.