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Tests if an expression is a number. If the expression is a number, the function returns True, otherwise the function returns False.
IsNumeric (Var)
Boolean
Var: An expression that you want to test.
Sub ExampleIsNumeric
Dim vVar As Variant
    vVar = "ABC"
    Print IsNumeric(vVar) ' False
    vVar = "123"
    Print IsNumeric(vVar) ' True
End Sub