Hi,
I need to be able to manipulate field values within a structure using
FieldInfo.GetVa lue and FieldInfo.SetVa lue, in VB.Nt 2003. The GetValue
is working fine and makes it really easy for me to maintain my code.
Unfortunately, SetValue doesn't return any errors but doesn't actually
set the value.
I have read through various newsgroup postings, and think the problem
might have something to do with "boxing", and passing of structures by
reference instead of by value. As such, I think I might be modifying a
copy of the structure, not the original structure itself. Even more
strange is that during my attempts to make it work, I found I could
issue a SetValue command within the Command Window in the VB.Net IDE
(and it would work), but the same code placed in the program did not
work. I suspect this is also to do with copies of the structure
instead of the original.
Anyway, the code below doesn't return any errors, but also doesn't set
the value! Please can somebody help me? I don't want to have to
redesign the code, and getting this working would make it really
efficient and easy to maintain
Thanks in advance
Laurie
Module module1
Structure ConfigVariables
Dim FirstVar As String
Dim SecondVar As String
Dim ThirdVar As String
End Structure
Sub Main()
Dim fld As System.Reflecti on.FieldInfo
Dim myType As Type = GetType(ConfigV ariables)
Dim myFields As System.Reflecti on.FieldInfo() = myType.GetField s()
For Each fld In myFields
fld.SetValue(CV , "Test Value")
Next fld
End Sub
3  3099 
Have tried various other ways to resolve this, but still to no avail.
Has anyone got any ideas? Thanks, Laurie
Have tried various other ways to resolve this, but still to no avail.
Has anyone got any ideas? Thanks, Laurie
Managed to answer my own question after reading some advice from Jay
at http://thedotnet.com/howto/work325581.aspx
The answer is to:
Dim cv1 As ValueType = CV
<then perform all SetValue operations on the cv1 object>
CV = cv1
....Sorted!!!
Thanks Jay
Laurie This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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