/// <summary>
        /// 删除数据
        /// </summary>
        /// <param>路径</param>
        /// <param>节点</param>
        /// <param>属性名，非空时删除该节点属性值，否则删除节点值</param>
        /// <param>值</param>
        /// <returns></returns>
        /**************************************************
         * 使用示列:
         * XmlHelper.Delete(path, "/Node", "")
         * XmlHelper.Delete(path, "/Node", "Attribute")
         ************************************************/
        public static void Delete(string path, string node, string attribute)
        {
            try
            {
                XmlDocument doc = new XmlDocument();
                doc.Load(path);
                XmlNode xn = doc.SelectSingleNode(node);
                XmlElement xe = (XmlElement)xn;
                if (attribute.Equals(""))
                    xn.ParentNode.RemoveChild(xn);
                else
                    xe.RemoveAttribute(attribute);
                doc.Save(path);
            }
            catch { }
        }
    }
}

==================================================

XmlFile.xml：
<?xml version="1.0" encoding="utf-8"?>
<Root />

==================================================

使用方法：

string xml = Server.MapPath("XmlFile.xml");
//插入元素
//XmlHelper.Insert(xml, "/Root", "Studio", "", "");
//插入元素/属性
//XmlHelper.Insert(xml, "/Root/Studio", "Site", "Name", "小路工作室");
//XmlHelper.Insert(xml, "/Root/Studio", "Site", "Name", "丁香鱼工作室");
//XmlHelper.Insert(xml, "/Root/Studio", "Site", "Name", "谱天城工作室");
//XmlHelper.Insert(xml, "/Root/Studio/Site[@Name='谱天城工作室']", "Master", "", "红尘静思");
//插入属性
//XmlHelper.Insert(xml, "/Root/Studio/Site[@Name='小路工作室']", "", "Url", "http://www.wzlu.com/");
//XmlHelper.Insert(xml, "/Root/Studio/Site[@Name='丁香鱼工作室']", "", "Url", "http://www.luckfish.net/");
//XmlHelper.Insert(xml, "/Root/Studio/Site[@Name='谱天城工作室']", "", "Url", "http://www.putiancheng.com/");
//修改元素值
//XmlHelper.Update(xml, "/Root/Studio/Site[@Name='谱天城工作室']/Master", "", "RedDust");
//修改属性值
//XmlHelper.Update(xml, "/Root/Studio/Site[@Name='谱天城工作室']", "Url", "http://www.putiancheng.net/");
//XmlHelper.Update(xml, "/Root/Studio/Site[@Name='谱天城工作室']", "Name", "PuTianCheng Studio");
//读取元素值
//Response.Write("<div>" + XmlHelper.Read(xml, "/Root/Studio/Site/Master", "") + "</div>");
//读取属性值
//Response.Write("<div>" + XmlHelper.Read(xml, "/Root/Studio/Site", "Url") + "</div>");
//读取特定属性值
//Response.Write("<div>" + XmlHelper.Read(xml, "/Root/Studio/Site[@Name='丁香鱼工作室']", "Url") + "</div>");
//删除属性
//XmlHelper.Delete(xml, "/Root/Studio/Site[@Name='小路工作室']", "Url");
//删除元素
//XmlHelper.Delete(xml, "/Root/Studio", "");