Null
The Null value is used to indicate a variable holds no
valid value. Similar to the Empty constant which indicates
a variable has not been defined yet, this constant indicates the
variable has been defined, but it has been defined to be holding
no valid value.
Dim sVar
' the following should fail - since sVar is Empty
If IsNull(sVar) Then Response.Write "1: Var is Null<BR>"
sVar = null
' the following should succeed - sVar is Null
If IsNull(sVar) Then Response.Write "2: Var is Null<BR>"
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