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dt.reset() destroys independent datarow in memory

I have noticed that doing a datatable.reset () wipes out an "independen tly"
declared datarow copied from a single datatable row. What is curious is
that if a dataset is substituted for the datatable, the "independen tly"
declared datarow is not destroyed. Is this difference in operation of
datatable vs. dataset by design or a Microsoft error?
Private drOriginal As DataRow 'independently declared datarow within same
form
Form paint function, where drOriginal is loaded:

Public Sub FormPaint(ByVal intActivityID As Integer)

Dim dt As New DataTable

Dim dr As DataRow

dt = dal.GetUserActi vityRowWithActi vityID(intActiv ityID) 'returns 1
row

For Each dr In dt.Rows

drOriginal = dr

Next

dt.Reset()
'subsequent processing reusing dt is not shown
dt = Nothing

End Sub
When a subsequent event needs to use drOriginal, drOriginal is empty (a
result of dt.Reset())

Again, if a dataset had been used instead of the datatable, drOriginal would
be subsequently intact.

Thanks,

Dean Slindee


May 16 '06 #1
1 2476
Dean,

Dt.clear and DS.clear are for me as well not the most sure commands.

I do mostly ds = new dataset to clear a dataset.
dt = new datatable

Cor

"Dean Slindee" <sl*****@charte r.net> schreef in bericht
news:kZ******** *****@fe04.lga. ..
I have noticed that doing a datatable.reset () wipes out an "independen tly"
declared datarow copied from a single datatable row. What is curious is
that if a dataset is substituted for the datatable, the "independen tly"
declared datarow is not destroyed. Is this difference in operation of
datatable vs. dataset by design or a Microsoft error?
Private drOriginal As DataRow 'independently declared datarow within
same form
Form paint function, where drOriginal is loaded:

Public Sub FormPaint(ByVal intActivityID As Integer)

Dim dt As New DataTable

Dim dr As DataRow

dt = dal.GetUserActi vityRowWithActi vityID(intActiv ityID) 'returns 1
row

For Each dr In dt.Rows

drOriginal = dr

Next

dt.Reset()
'subsequent processing reusing dt is not shown
dt = Nothing

End Sub
When a subsequent event needs to use drOriginal, drOriginal is empty (a
result of dt.Reset())

Again, if a dataset had been used instead of the datatable, drOriginal
would be subsequently intact.

Thanks,

Dean Slindee


May 16 '06 #2

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