Hi,

I'm trying to store a small dataset in the ViewState object, so I don't have to repopulate it every time the form is posted back.

After populating the dataset for the first time, I'm able to do a statement like...

ViewState("ds") = ds.GetXml

which stores the dataset as xml inside a string. No problem.

How then can I repopulate the dataset when the page is posted back?

I've got

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        If IsPostBack = False Then
          'Do all my dataset population stuff here
          ViewState("ds") = ds.GetXml
        Else
           'populate dataset with html from ViewState string
           ds.ReadXml(ViewState("ds"))
        End If

Nope. No dice. ASP.NET doesn't want a string passed into the ReadXml method. It wants an XmlReader. I tried messing around with this a little bit, but got no success. You'd think that if you can write a dataset out to a string, you could then read it from a string.

I just want to store a dataset in a ViewState or Session variable. How do I do this???

Thanks.

Aaron
 End Sub

Check that the ViewState("ds") exists first.

Brian

I figured it out. It was

       If IsPostBack = False Then
          'Do all my dataset population stuff here
          ViewState("ds") = ds.GetXml
        Else
          'get xml back from ViewState
          Dim vxml As String = ViewState("ds")
          Dim sr As New System.IO.StringReader(vxml)
          'read in XML from stream
          ds.ReadXml(sr)
        End If

It was the old StringReader thing. Seems like a silly extra step to me. If you can write to a string, you ought to be able to read from a string.

Thanks all.

Aaron

Or better yet, just store the DataSet object directly to the session. The DataSet stores its data internally as XML anyway so there's probably not much difference between storing as a string of XML from the dataset or the dataset object itself, particularly with a simple single-table dataset.

-Peter