问题
Does any one know if C# has an equivalent of ObjPtr from VB6, or equivalent functionality (see more info below)? Here are a couple of links to info on ObjPtr devx , thevbzone.
Basically I have a third party treeview that I need to walk thru to get specific nodes but the only (relevant) info the nodes have is name ... but the node names don't need to be unique. So I need to get a unique value for each node as I walk thru it the first time so when I walk thru it again I know which is which. In the old school VB6 days I would use ObjPtr.
回答1:
If they're objects, why not just store the object references directly? These will be unique.
You can use Object.ReferenceEquals(x, y) to determine if a reference you have stored is referring to the same object you just retrieved from the tree.
回答2:
The closest direct equivalent I can think of would be to use a GCHandle to get an IntPtr for your object reference.
You would need to allocate a GCHandle for your object (GCHandle.Alloc), then use GCHandle.ToIntPtr to convert to an IntPtr. The linked documentation shows the process.
回答3:
If the treenode has FullPath property, you can use it to uniquely identify a node in the treeview (Winforms Treeview has the FullPath property). This won't be unique if 2 siblings have same text in it.
OR
You could use Handle property of the TreeNode.
回答4:
GetHashCode should work well for testing unique values unless the third-party has overriden the Object implementation with something that doesn't make sense in your scenario.
I would assume that nodes in the tree would define equality/hashcode by more than just the value string, but you would need to check.
来源：https://stackoverflow.com/questions/1374664/equivalent-functionality-of-objptr-from-vb6-in-c