salve ragazzi.. da qualche giorno sto cercando soluzioni a come aggiornare un file XML.
sulla rete ho trovato questo codice:
<%@ Import Namespace="System.XML" %>
<%@ Page Language="vb" AutoEventWireup="false" Codebehind="WebForm1.aspx.vb" Inherits="xml.WebForm1"%>
<HTML>
<HEAD>
<script language="VB" id="Script1" runat="server">
Sub btnReadXML_OnClick(sender As Object, e As EventArgs)
'Read and display existing file
ReadXML(Server.MapPath("menu.xml"))
End Sub
Sub btnWriteXML_OnClick(sender As Object, e As EventArgs)
Try
Dim enc as Encoding
'Create file, overwrite if exists
'enc is encoding object required by constructor
'It is null, so default encoding is used
Dim objXMLTW as new XMLTextWriter(Server.MapPath("mdb-database/applicant.xml"), enc)
objXMLTW.WriteStartDocument
'Top level (Parent element)
objXMLTW.WriteStartElement("images")
objXMLTW.WriteStartElement("pic")
'Child elements, from request form
objXMLTW.WriteStartElement("Name")
objXMLTW.WriteString(Request("txtName"))
objXMLTW.WriteEndElement
objXMLTW.WriteStartElement("Address")
objXMLTW.WriteString(Request("txtAddress"))
objXMLTW.WriteEndElement
objXMLTW.WriteStartElement("City")
objXMLTW.WriteString(Request("txtCity"))
objXMLTW.WriteEndElement
objXMLTW.WriteStartElement("State")
objXMLTW.WriteString(Request("txtState"))
objXMLTW.WriteEndElement
objXMLTW.WriteStartElement("Zip")
objXMLTW.WriteString(Request("txtZip"))
objXMLTW.WriteEndElement
objXMLTW.WriteEndElement 'End top level element
objXMLTW.WriteEndDocument 'End Document
objXMLTW.Flush 'Write to file
objXMLTW.Close
'Display File Just Created
ReadXML(Server.MapPath("applicant.xml"))
Catch Ex as Exception
lblXMLFile.Text = "The following error occurred: " & Ex.Message
End Try
End Sub
Sub ReadXML(FileName as String)
Try
lblXMLFile.Text =""
Dim objXMLTR as new XMLTextReader(FileName)
dim sCategory as String
dim bNested as Boolean
dim sLastElement as String
Dim sValue as String
'Read method loops through the XML stream
Do While objXMLTR.Read
'Output elements and values
'Look at output in browser and compare to menu.xml file to
'see exactly what is being done
If objXMLTR.NodeType = XMLNodeType.Element Then
if bNested = True then
if sCategory <> "" then sCategory = sCategory & " > "
sCategory = sCategory & sLastElement
End if
bNested = True
sLastElement = objXMLTR.Name
Else If objXMLTR.NodeType = XMLNodeType.Text or _
objXMLTR.NodeType = XMLNodeType.CData Then
bNested = False
sCategory = "<P>" & sCategory
sValue = objXMLTR.value
lblXMLFile.Text = lblXMLFile.Text & "<B>" & sCategory & _
"<BR>" & sLastElement & "</B><BR>" & sValue
sLastElement = ""
sCategory = ""
End if
Loop
objXMLTR.close
Catch Ex as Exception
lblXMLFile.Text = "The following error occurred: " & Ex.Message
End Try
End Sub
</script>
</HEAD>
<body>
<center><b>XML Text Reader/Text Writer Demo</b></center>
<form id="Form1" action="XML_DEMO.aspx" method="post" runat="server">
<table width="100%">
<tr>
<TD width="50%" valign="top">
Click below to read/parse the file "menu.xml".<p>
<asp:Button id="btnReadXML" text="Read XML Document" OnClick="btnReadXML_onClick" runat="server" />
<p>
<asp:label id="lblXMLFile" runat="server" /></p>
</TD>
<TD width="50%" valign="top">
Complete the fields below to create and display the XML file "applicant.xml"
(write permission for the Internet Anonymous user must be enabled)<P>
<asp:Button id="btnWriteXML" text="Write XML Document" OnClick="btnWriteXML_onClick" runat="server" />
<p><strong>Applicant</strong>
<p><table>
<tr>
<td>
Name:</td>
<td><asp:Textbox id="txtName" runat="server" width="200" visible="True"></asp:Textbox></td>
</tr>
<tr>
<td>Address:
</td>
<td>
<asp:Textbox id="txtAddress" runat="server" visible="True" width="200" /></td>
</tr>
<tr>
<td>
City:
</td>
<td>
<asp:Textbox id="txtCity" runat="server" width="200" visible="True"></asp:Textbox></td>
</tr>
<tr>
<td>
State:
</td>
<td>
<asp:Textbox id="txtState" runat="server" width="200" visible="True" MaxLength="2"></asp:Textbox></td>
</tr>
<tr>
<td>
Zip:
</td>
<td>
<asp:Textbox id="txtZip" runat="server" width="200" visible="True" maxlength="10"></asp:Textbox></td>
</tr>
</table>
</p>
</TD>
</tr>
</table>
</form>
</body>
</HTML>
Il codice funge benissimo.
Ora la mia problematica è in questo punto:
_________________________________________
'Create file, overwrite if exists
'enc is encoding object required by constructor
'It is null, so default encoding is used
Dim objXMLTW as new XMLTextWriter(Server.MapPath("mdb-database/applicant.xml"), enc)
_______________________________________________
in quanto ogni qualvolta si esegue la Form il file XMl Generato viene sovrascritto con i nuovi dati inseriti.
L'ideale sarebbe quello di solo
aggiungere degli elementi FIGLIO.
Spero che sono stato chiaro....
Grazie in anticipo dell'aiuto
Horus76
