以下是我的xml文件代码
<XMLFile> <EMail> <From> <Address>dddd@acd.com</Address> </From> <Receipent> <To>eeee@qwe.com</To> </Receipent> <Subject>fffffsadasd</Subject> <Body>ggggasdsd</Body> </EMail> </XMLFile>
我已经发送了一个按钮。每次我想要将Enail节点和相应的子节点添加到现有的xml文件时点击该按钮。 在发送按钮时，我写了以下代码。
Dim currNode As XmlNode
Dim doc As New XmlDocument
doc.LoadXml(("<XMLFile>" + " <EMail></EMail>" + "</XMLFile>"))
Dim docFrag As XmlDocumentFragment = doc.CreateDocumentFragment()
docFrag.InnerXml = "<From>" + " <Address>" + txtFrom.Text + " </Address>" + "</From>"
currNode = doc.DocumentElement.FirstChild
currNode.InsertAfter(docFrag, currNode.LastChild)
docFrag.InnerXml = "<Receipent>" + " <To>" + txtTo.Text + " </To>" + "</Receipent>"
currNode = doc.DocumentElement.FirstChild
currNode.InsertAfter(docFrag, currNode.LastChild)
docFrag.InnerXml = "<Subject>" + txtSubject.Text + "</Subject>"
currNode = doc.DocumentElement.FirstChild
currNode.InsertAfter(docFrag, currNode.LastChild)
docFrag.InnerXml = "<Body>" + txtBody.Text + "</Body>"
currNode = doc.DocumentElement.FirstChild
currNode.InsertAfter(docFrag, currNode.LastChild)
doc.Save("C:\xmlmailfile.xml")
我需要在按钮点击中进行哪些修改
答案 0 :(得分：2)
这样的事情应该这样做。尽管如此，XMLTextWriter可能更适合您的目的：
Private Function GenerateXML(ByVal emails As List(Of Email)) As String
Dim sb As New System.Text.StringBuilder
Using sw As New IO.StringWriter(sb), xt As New Xml.XmlTextWriter(sw)
xt.WriteStartElement("xmlDoc")
For i As Integer = 0 To emails.Count - 1
xt.WriteStartElement("email")
xt.WriteStartElement("From")
xt.WriteElementString("address", emails(i).From)
xt.WriteEndElement()
xt.WriteStartElement("Receipent")
xt.WriteElementString("to", emails(i).Recipient)
xt.WriteEndElement()
xt.WriteElementString("subject", emails(i).Subject)
xt.WriteElementString("body", emails(i).Body)
xt.WriteEndElement()
Next
xt.WriteEndElement()
End Using
Return sb.ToString
End Function
修改
这需要错误处理等，但应该适合你。在某些情况下，它会破坏（例如，如果文件存在但是为空），您需要自己解决。
Module consoleTestApp
Private _path As String = "c:\output.xml"
//Just pretend these are text boxes
Public txtFrom As String
Public txtRecipient As String
Public txtSubject As String
Public txtBody As String
Sub Main()
txtFrom = "from1"
txtRecipient = "rec1"
txtSubject = "subj1"
txtBody = "body1"
AddNewEmail()
txtFrom = "from2"
txtRecipient = "rec2"
txtSubject = "subj2"
txtBody = "body2"
AddNewEmail()
End Sub
Private Sub AddNewEmail()
If Not IO.File.Exists(_path) Then
Using xt As New Xml.XmlTextWriter(_path, System.Text.Encoding.UTF8)
xt.WriteStartElement("xmlDoc")
xt.WriteEndElement()
End Using
End If
Dim xD As New Xml.XmlDocument
xD.Load(_path)
Dim xN As Xml.XmlNode = xD.CreateNode(Xml.XmlNodeType.Element, String.Empty, "email", String.Empty)
xN.InnerXml = GenerateXML()
xD.SelectSingleNode("//xmlDoc").AppendChild(xN)
xD.Save(_path)
End Sub
Private Function GenerateXML() As String
Dim sb As New System.Text.StringBuilder
Using sw As New IO.StringWriter(sb), xt As New Xml.XmlTextWriter(sw)
xt.WriteStartElement("From")
xt.WriteElementString("address", txtFrom)
xt.WriteEndElement()
xt.WriteStartElement("Receipent")
xt.WriteElementString("to", txtRecipient)
xt.WriteEndElement()
xt.WriteElementString("subject", txtSubject)
xt.WriteElementString("body", txtBody)
End Using
Return sb.ToString
End Function
End Module