datasets to xml 1

[SMURF75]

Hi

I just cant get this to work. The idea is to add a user to an xmlfile. It works when when a new file is created. But when i want to add a dataset to an existing file it fails.

Try
       
            Dim dsSet As New DataSet("Users")
            Dim dtTables As New DataTable("User")
            Dim drRow As DataRow

            dtTables.Columns.Add("UserId", System.Type.GetType("System.Int32"))
            dtTables.Columns.Add("Password", System.Type.GetType("System.String"))
            dtTables.Columns.Add("FName", System.Type.GetType("System.String"))
            dtTables.Columns.Add("LName", System.Type.GetType("System.String"))

            drRow = dtTables.NewRow()
            drRow("UserId") = txtUserID.Text
            drRow("Password") = txtPassword.Text
            drRow("FName") = txtFName.Text
            drRow("LName") = txtLName.Text

            dtTables.Rows.Add(drRow)

            dsSet.Tables.Add(dtTables)

            saveDataSet(dsSet)

            Me.Close()

        Catch ex As Exception
            logError(ex)
        End Try

    End Sub



Public Function saveDataSet(ByVal ds As DataSet) As Boolean

        Try
            strPath = Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly(). _
            GetName().CodeBase)
            strPath = strPath & "\" & "users2.xml"

            Dim fs As New FileStream(strPath, FileMode.OpenOrCreate, FileAccess.Write)

            Dim xw As New XmlTextWriter(fs, System.Text.Encoding.UTF8)

            ds.WriteXml(xw,    System.Data.XmlWriteMode.WriteSchema)

            xw.Close()

        Catch ex As Exception
            Throw ex
        End Try

End Function

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Im three apples high, Im blue, and i most certainly like that cold beer that should be every mans right after a hard days work!

 

[ThatRickGuy]

First I would say, avoid using this folder:

Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly(). _
            GetName().CodeBase)

If the app is installed in the program files folder, there can and often enough will be security issues with writing to the app.

I would recommend:

'for user specific settings storage
Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData)
'or for application specific settings storage
Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData)

Also, you don't need to create the file stream or XML reader. you can use:

ds.WriteXml(strPath, System.Data.XmlWriteMode.WriteSchema)

also, you will likely want to read in the XML file before writing it, as writing it will overwrite it I beleive.

And what may be causing your issue, if the file is open, you will not be able to write to it.

-Rick

----------------------

http://www.ringdev.com

I believe in killer coding ninja monkeys.

 

[SMURF75]

I was starting to think that way.... open first then add then rewrite. Now I know.. thx! The other tips were also useful.

plaff.. a star on your forehead

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Im three apples high, Im blue, and i most certainly like that cold beer that should be every mans right after a hard days work!