Syntax
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object Is [object | Nothing]
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Description
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Returns
True
if the two operands refer to the same object; returns
False
otherwise.
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Comments
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This operator is used to determine whether two object variables refer to the same object. Both operands must be object variables of the same type (i.e., the same data object type or both of type
Object
).
The
Nothing
constant can be used to determine whether an object variable is uninitialized:
If MyObject Is Nothing Then MsgBox "MyObject is uninitialized."
Uninitialized object variables reference no object.
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Example
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This function inserts the date into a Microsoft Word document.
Sub InsertDate(ByVal WinWord As Object)
If WinWord Is Nothing Then
MsgBox "Object variant is not set."
Else
WinWord.Insert Date$
End If
End Sub
Sub Main()
Dim WinWord As Object
On Error Resume Next
WinWord = CreateObject("word.basic")
InsertDate WinWord
End Sub
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See Also
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Operator Precedence (topic); Like (operator).
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Platform(s)
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All.
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Notes
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When comparing OLE automation objects, the
Is
operator will only return
True
if the operands reference the same OLE automation object. This is different from data objects. For example, the following use of
Is
(using the object class called
excel.application
) returns
True
:
Dim a As Object
Dim b As Object
a = CreateObject("excel.application")
b = a
If a Is b Then Beep
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|
The following use of
Is
will return
False
, even though the actual objects may be the same:
Dim a As Object
Dim b As Object
a = CreateObject("excel.application")
b = GetObject(,"excel.application")
If a Is b Then Beep
The
Is
operator may return
False
in the above case because, even though
a
and
b
reference the same object, they may be treated as different objects by OLE 2.0 (this is dependent on the OLE 2.0 server application).
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