读写xml文件的2个小函数

#region 读写xml文件的2个小函数，2005 4 2 by hyc

  public void SetXmlFileValue(string xmlPath,string AppKey,string AppValue)//写xmlPath是文件路径+文件名，AppKey是 Key Name，AppValue是Value
   {
    XmlDocument xDoc = new XmlDocument();
    xDoc.Load(xmlPath);
    XmlNode xNode;
    XmlElement xElem1;
    XmlElement xElem2;

   xNode =  xDoc.SelectSingleNode("//appSettings");

   xElem1 = (XmlElement)xNode.SelectSingleNode("//add[@key='" + AppKey + "']");
    if ( xElem1 != null )
    {
     xElem1.SetAttribute("value",AppValue);
    }
    else
    {
     xElem2 = xDoc.CreateElement("add");
     xElem2.SetAttribute("key",AppKey);
     xElem2.SetAttribute("value",AppValue);
     xNode.AppendChild(xElem2);
    }
    xDoc.Save(xmlPath);
   }

   public void GetXmlFileValue(string xmlPath,string AppKey,ref string AppValue)//读xmlPath是文件路径+文件名，AppKey是 Key Name，AppValue是Value
   {
    XmlDocument xDoc = new XmlDocument();
    xDoc.Load(xmlPath);
    XmlNode xNode;
    XmlElement xElem1;

   xNode =  xDoc.SelectSingleNode("//appSettings");

   xElem1 = (XmlElement)xNode.SelectSingleNode("//add[@key='" + AppKey + "']");
    if ( xElem1 != null )
    {
     AppValue=xElem1.GetAttribute ("value");
    }
    else
    {
//    MessageBox.Show ("There is not any information!");
    }

  }

  #endregion