Err.Clear Method

   
Err.Clear Method

Class

Microsoft.VisualBasic.ErrObject

Syntax

 Err.Clear(  ) 

Description

Explicitly resets all the properties of the Err object after an error has been handled

Rules at a Glance

You need to clear the Err object only if you need to reference its properties for another error within the same subroutine, or before another On Error statement within the same subroutine.

Example

 On Error Resume Next     i = oObjectOne.MyFunction(iVar)      If Err.Number <> 0 Then    MsgBox ("The Error : " & Err.Description & vbCrLf _           & " was generated in " & Err.Source)    Err.Clear End If      j = oObjectTwo.YourFunction(iVar)     If Err.Number <> 0 Then    MsgBox ("The Error : " & Err.Description & vbCrLf _           & " was generated in " & Err.Source)    Err.Clear End If 

Programming Tips and Gotchas

  • Resetting the Err object explicitly using the Clear method is necessary in situations where you are using On Error Resume Next and are testing the value of Err.Number repeatedly. Unless you reset the Err object, you run the very real risk of catching the previously handled error, the details of which are still lurking in the Err object's properties.

  • The Err object is automatically reset when either a Resume , Exit Sub , Exit Function , Exit Property , or On Error statement is executed.

  • You can achieve the same results by setting the Err.Number property to 0; however, your code will be more readable if you use the Clear method.

  • VB also supports structured error-handling through the Try...Catch... Finally statement.

  • Internally, in VB.NET the Err object is an instance of the Microsoft.VisualBasic.ErrObject class. It is returned by the Err property of the Microsoft.VisualBasic.Information class.

See Also

Err.Raise Method

   


VB.Net Language in a Nutshell
VB.NET Language in a Nutshell
ISBN: B00006L54Q
EAN: N/A
Year: 2002
Pages: 503

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net