/**
* @brief Cast an arbitrary object to the given interface.
* @param ob = object to be cast of unknown type
* @returns ob cast to the interface type
*/
public static Delegate[] CastObj2IFace(object ob, string ifacename)
{
if (ob == null)
{
return(null);
}
/*
* If it is already one of our interfaces, extract the script-defined class object from it.
*/
if (ob is Delegate[])
{
Delegate[] da = (Delegate[])ob;
ob = da[0].Target;
}
/*
* Now that we have a presumed script-defined class object, cast that to the requested interface
* by picking the array of delegates that corresponds to the requested interface.
*/
XMRSDTypeClObj ci = (XMRSDTypeClObj)ob;
int iFaceIndex = ci.sdtcClass.intfIndices[ifacename];
return(ci.sdtcITable[iFaceIndex]);
}
/**
* @brief Perform runtime casting of XMRSDTypeClObj's.
* @param ob = XMRSDTypeClObj of unknown script-defined class to cast
* @param classindex = script-defined class to cast it to
* @returns ob is a valid instance of classindex; else exception thrown
*/
public static XMRSDTypeClObj CastClass2Class(object ob, int classindex)
{
/*
* Let mono check to see if we at least have an XMRSDTypeClObj.
*/
XMRSDTypeClObj ci = (XMRSDTypeClObj)ob;
if (ci != null)
{
/*
* This is the target class, ie, what we are hoping the object can cast to.
*/
TokenDeclSDTypeClass tc = (TokenDeclSDTypeClass)ci.xmrInst.m_ObjCode.sdObjTypesIndx[classindex];
/*
* Step from the object's actual class rootward.
* If we find the target class along the way, the cast is valid.
* If we run off the end of the root, the cast is not valid.
*/
for (TokenDeclSDTypeClass ac = ci.sdtcClass; ac != tc; ac = ac.extends)
{
if (ac == null)
{
throw new InvalidCastException("invalid cast from " + ci.sdtcClass.longName.val +
" to " + tc.longName.val);
}
}
/*
* The target class is at or rootward of the actual class,
* so the cast is valid.
*/
}
return(ci);
}
