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'**********************************************************************************************************
' Name: isEmptyString
' Author: mielk | 2014-09-20
'
' Description: Function to check if the given value is empty string.
' Note that strings consisting only of blank characters (i.e. spaces) are also
' considered to be an empty string.
'
' Parameters:
' value Value to be checked.
'
'
' Returns:
' Boolean True - if the given value is empty or cannot be converted to String type.
' True value is returned in a few cases:
' * the source parameter [value] is an empty string,
' * the source parameter [value] is a string consisting only of blank characters,
' * the source parameter [value] is not a string and cannot be converted into
' string (i.e it is object or array).
' False - if the given value is a non-empty string or other primitive value that can
' be converted into String.
'
'
'
' --- Changes log -----------------------------------------------------------------------------------------
' 2014-09-20 mielk Function created.
'**********************************************************************************************************
Public Function isEmptyString(ByVal value As Variant) As Boolean
Const METHOD_NAME As String = "isEmptyString"
'------------------------------------------------------------------------------------------------------
'First check if the given value can be converted into String. If not, function should return --------|
'True, so the code moves to the [NotStringException] label, change the value of function to '|
'True and leaves the function. '|
On Error GoTo NotStringException '|
value = VBA.CStr(value) '|
On Error GoTo 0 '|
'----------------------------------------------------------------------------------------------------|
'Check different cases when the function should return True. ----------------------------------------|
If VBA.IsMissing(value) Then '|
isEmptyString = True '|
ElseIf VBA.isEmpty(value) Then '|
isEmptyString = True '|
ElseIf VBA.Len(VBA.Trim(value)) = 0 Then '|
isEmptyString = True '|
End If '|
'----------------------------------------------------------------------------------------------------|
'==========================================================================================================
ExitPoint:
Exit Function
'----------------------------------------------------------------------------------------------------------
NotStringException:
isEmptyString = True
GoTo ExitPoint
End Function