IsError (function)




Returns True if expression is a user-defined error value; returns False otherwise.


This example creates a function that divides two numbers. If there is an error dividing the numbers, then a variant of type "error" is returned. Otherwise, the function returns the result of the division. The IsError function is used to determine whether the function encountered an error.

Function Div(ByVal a,ByVal b) As Variant
  If b = 0 Then
    Div = CVErr(2112)  'Return a special error value.
    Div = a / b    'Return the division.
  End If
End Function

Sub Main()
  Dim a As Variant
  a = Div(10,12)
  If IsError(a) Then
    MsgBox "The following error occurred: " & CStr(a)
    MsgBox "The result of the division is: " & a
  End If
End Sub

See Also

Variant (data type); IsEmpty (function); IsDate (function); IsObject (function); VarType (function); IsNull (function).

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