更新或追加子 XML 文件

问：

我已经尝试了一切方法，用我的表单中的新数据更新XML文件中的子项。 我有一个表单，如果有 XML 文件，它首先将数据从 XML 读取到表单字段中。 如果没有 XML 文件，它将创建一个新的 XML 文件，并在子项中附加表单中的数据。

我的问题是用新数据更新孩子，我不能这样做，我可以用System.Web.UI.WebControls.TextBox获取文本，也可以获取一个空字段。

然后我想我可以删除子节点并创建新的子节点，但它们只是空的！ 有人能告诉我为什么吗？

这是我的XML文件

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<CGTemplateDATA>
  <title>Title here</title>
  <text>Text here</text>
  <reference>Reference here</reference>
</CGTemplateDATA>

这是我的aspx文件

<%@ Page Language="C#" Debug="true" %>
<%@ Import Namespace="System.Xml" %>

<script runat="server">
    protected void Save(object sender, EventArgs e)
    {
        //this.txtReference.Text = DateTime.Now.ToString("hh:mm:ss");
        this.txtReference.Text = "Læs mere på tvsyd.dk";
    }

    protected void Page_Load(object sender, EventArgs e)
    {
        string xmlPath = MapPath("xml/feed.xml");
        XmlDocument xmldoc = new XmlDocument();
        if (System.IO.File.Exists(xmlPath))
        {
            xmldoc.Load(xmlPath); 
            XmlNode nodeTitle = xmldoc.DocumentElement.SelectSingleNode("title");
            txtTitle.Text = nodeTitle.InnerText;
            XmlNode nodeText = xmldoc.DocumentElement.SelectSingleNode("text");
            txtText.Text = nodeText.InnerText;
            XmlNode nodeRef = xmldoc.DocumentElement.SelectSingleNode("reference");
            txtReference.Text = nodeRef.InnerText;
            lblResult.Text = "Opdater teksten i XML dokumentet";
        }
    }
</script>


<script runat="server">
    protected void btnSave_Click(object sender, EventArgs e)
    {
        string xmlPath = MapPath("xml/feed.xml");
        XmlDocument doc = new XmlDocument();

        //Check if the file already exists or not
        if (System.IO.File.Exists(xmlPath))
        {

            //XmlDocument doc = new XmlDocument();
            doc.Load(xmlPath);

            XmlNode nodeTitle = doc.SelectSingleNode("/CGTemplateDATA/title");
            XmlNode nodeText = doc.SelectSingleNode("/CGTemplateDATA/text");
            XmlNode nodeReference = doc.SelectSingleNode("/CGTemplateDATA/reference");
XmlNode parent = doc.SelectSingleNode("/CGTemplateDATA");
parent.RemoveChild(nodeTitle);
parent.RemoveChild(nodeText);
parent.RemoveChild(nodeReference);

            XmlNode parentNode = CreateNewBookNode(doc);                        
            //Append the cgtemplatedata node to the document
            doc.AppendChild(parentNode);

            doc.Save(xmlPath);

        }
        else
        {            
            XmlNode declarationNode = doc.CreateXmlDeclaration("1.0", "utf-8", "yes");
            doc.AppendChild(declarationNode);
            XmlNode bookNode = CreateBookNode(doc);                        
            //Append the cgtemplatedata node to the document
            doc.AppendChild(bookNode);
            lblResult.Text = "XML dokumentet er hermed oprettet";
            doc.Save(xmlPath);
        }
    }

    XmlNode CreateBookNode(XmlDocument doc)
    {
        XmlNode bookNode = doc.CreateElement("CGTemplateDATA");
        //Add all the children of the book node            
        XmlNode titleNode = doc.CreateElement("title");
        titleNode.InnerText = txtTitle.Text;
        bookNode.AppendChild(titleNode);

        XmlNode textNode = doc.CreateElement("text");
        textNode.InnerText = txtText.Text;
        bookNode.AppendChild(textNode);

        XmlNode referenceNode = doc.CreateElement("reference");
        referenceNode.InnerText = txtReference.Text;
        bookNode.AppendChild(referenceNode);

        return bookNode;
    }

    XmlNode CreateNewBookNode(XmlDocument doc)
    {
XmlNode parentNode = doc.SelectSingleNode("/CGTemplateDATA");
        XmlNode titleNode = doc.CreateElement("title");
        titleNode.InnerText = txtTitle.Text;
        parentNode.AppendChild(titleNode);

        XmlNode textNode = doc.CreateElement("text");
        textNode.InnerText = txtText.Text;
        parentNode.AppendChild(textNode);

        XmlNode referenceNode = doc.CreateElement("reference");
        referenceNode.InnerText = txtReference.Text;
        parentNode.AppendChild(referenceNode);

        return parentNode;
    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Storke-TV tekst</title>
    <link href="css/stylesheet.css" rel="stylesheet" type="text/css" />
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <img alt="" class="style5" src="images/storke_tekst_top.png" /><br />
    <br />
        <table>
            <tr>
                <td colspan="2" style="width: 586px">
                    <b>FORSIGTIG! Denne side giver direkte adgang til at opdatere storke tekst.</b><br />
                    <br />
                    1: Udfyld felterne.<br />
                    2: Tryk på GEM TEKST.<br />
                    3: Hvis du vil opdatere teksten, så ret den, og tryk på GEM TEKST igen.<br />
                </td>                               
            </tr>
            <tr>
                <td colspan="2" style="width: 586px">&nbsp;</td>                               
            </tr>
            <tr>
                <td style="width: 85px; height: 40px">
                    Overskrift:
                </td>
                <td style="width: 501px; height: 40px">
                    <asp:TextBox ID="txtTitle" runat="server" Width="182px" Height="28px" Text="temp" />
                </td>
            </tr>
            <tr>
                <td style="width: 85px; height: 41px">
                    Tekst:
                </td>
                <td style="width: 501px; height: 152px">
                    <asp:TextBox ID="txtText" Textmode="Multiline" runat="server" Width="240px" height="150" />
                </td>
            </tr>
            <tr>
                <td style="width: 85px; height: 41px">
                    Henvisning:
                </td>
                <td style="width: 501px; height: 54px">
                    <asp:TextBox ID="txtReference" Textmode="Multiline" runat="server" Width="240px" Height="42px" />
                    &nbsp;<&nbsp;<asp:Button Text="Indsæt web henvisning" runat="server" ID="btnReftxt" Width="142px" Height="24" font-size="12px" OnClick="Save" />
                </td>
            </tr>
            <tr>
                <td style="width: 85px; height: 41px">
                    &nbsp;
                </td>
                <td style="width: 586px; height: 52px">
                    <asp:Button Text="GEM TEKST" runat="server" ID="btnSave" Width="240px" Height="40" OnClick="btnSave_Click" />
                </td>                
            </tr>
            <tr>
                <td style="width: 85px; height: 41px">
                    &nbsp;
                </td>
                <td style="width: 586px; height: 41px">
                    <asp:Label Text="Gem tekst" runat="server" ID="lblResult" Width="295px"></asp:Label>
                </td>                
            </tr>
        </table>
    </div>
    </form>
</body>
</html>