NULL object in vb.net
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Thread: NULL object in vb.net

  1. #1
    Join Date
    Feb 2008
    Posts
    12

    Question NULL object in vb.net

    how to check whether an object/string exist....

    if possible help me with a code

  2. #2
    Join Date
    Jul 2006
    Location
    Germany
    Posts
    3,723

    Re: NULL object in vb.net

    With an object you usually do If ObjectVar Is Nothing Then...
    A string could be checked for empty like If StringVar = vbNullString Then
    where also If StringVar = "" Then... gives the same result, I think.

  3. #3
    Join Date
    Jun 2005
    Location
    JHB South Africa
    Posts
    3,772

    Re: NULL object in vb.net

    Quote Originally Posted by WoF
    With an object you usually do If ObjectVar Is Nothing Then...
    A string could be checked for empty like If StringVar = vbNullString Then
    where also If StringVar = "" Then... gives the same result, I think.
    100% correct.

    the only difference is a Null string has no allocated memory, and can cause errors when passed to a API.

    check under NULL's in this article for more info..

    Gremmy..
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