Question

我正在尝试将一些值存储到xml文件中。我已经创建了一个Xml文件并尝试覆盖数据。代码给出..

/*storepassword.cs *//

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;

public class StorePassword
{
    public StorePassword()
    {
    }
    public void  store(NewPassword nps)
    {
       XmlDocument XmlDoc = new XmlDocument();

       //XmlDoc.Load(@"Password.xml");
       XmlDoc.LoadXml("Password.xml");

       XmlNode root = XmlDoc.DocumentElement;
       XmlNode myNode1 = root.SelectSingleNode("UserName");
       XmlNode myNode2 = root.SelectSingleNode("PassWord");
       myNode1.Value = "sjn";
       myNode2.Value = "sjn123";
       XmlDoc.Save(@"Password.xml");
   }
}

//NewPassword.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

public class NewPassword
{

    public NewPassword()
    {

    }
    public string username{ get; set; }
    public string Password{ get; set; }
}

按钮点击..

NewPassword nps = new NewPassword();
nps.username = TxtUser.Text;
nps.Password = TxtNewPassword.Text;
StorePassword sp=new StorePassword();
sp.store(nps);

现有的Xml文件包含以下内容..

<?xml version="1.0" encoding="utf-8"?>
<ROOT>
  <UserName>abc</UserName>
  <PassWord>123</PassWord>
</ROOT>

但它不起作用..

根级别的数据无效。第1行，第1位

发生此错误..

将代码改为XmlDoc.Load(@"Password.xml");

现在错误已更改为

Root element is missing.

   Description: An unhandled exception occurred during the execution of the current web                  request. Please review the stack trace for more information about the error and where it   originated in the code. 

Exception Details: System.Xml.XmlException: Root element is missing.

为什么会这样？

Answer 1

尝试使用XML序列化：

public static partial class ObjectXMLSerializer<T> where T : class
{
            private static void SaveToDocumentFormat(T serializableObject, System.Type[] extraTypes, string path, IsolatedStorageFile isolatedStorageFolder)
            {
                using (TextWriter textWriter = CreateTextWriter(isolatedStorageFolder, path))
                {
                    XmlSerializer xmlSerializer = CreateXmlSerializer(extraTypes);

                    //Cuong: set name space to null
                    XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
                    ns.Add("", "");
                    xmlSerializer.Serialize(textWriter, serializableObject, ns);
                }
            }
            public static void Save(T serializableObject, string path)
            {
                    SaveToDocumentFormat(serializableObject, null, path, null);
            }

}

Answer 2

加载Xml时，需要使用Server.MapPath。 XmlDoc.LoadXml(Server.MapPath("Password.xml"));

Answer 3

删除

<?xml version="1.0" encoding="utf-8"?>

这

<?xml version="1.0" encoding="utf-8"?>
<ROOT>
  <UserName>abc</UserName>
  <PassWord>123</PassWord>
</ROOT>

我不知道它为什么会起作用，但我们会在代码中一直这样做。是的，您应该使用XmlDocument.Load而不是XmlDocument.LoadXml

使用Asp-C写入Xml文件＃

3 个答案: