C# 關於XML遍曆新增節點，修改屬性小例

<?xml version="1.0" encoding="gb2312"?>
<bookstore>
  <book genre="李2紅" ISBN="2-3631-4">
    <title>CS從入門到精通</title>
    <author>候捷</author>
    <price>58.3</price>
  </book>
  <book genre="李讚紅" ISBN="2-3631-4">
    <title>CS從入門到精通</title>
    <author>小六</author>
    <price>58.3</price>
  </book>
  <book45 genre="李讚紅" ISBN="2-3631-4">
    <title>CS從入門到精通</title>
    <author>大黃</author>
    <price>58.3</price>
  </book45>
</bookstore>

測試代碼：

	    XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load("E:\\bookstore.xml");
	    //獲取bookstore節點的所有子節點
            XmlNodeList nodeList = xmlDoc.SelectSingleNode("bookstore").ChildNodes;
            for (int i = 0; i < nodeList.Count; i++)//遍曆每個book節點
            {   //將子節點類型轉換為XmlElement類型
                XmlElement xe = (XmlElement)nodeList.Item(i);
                if (xe.Name == "book")
                {   //如果genre屬性值為“李讚紅”
                    if (xe.GetAttribute("genre") == "李讚紅")
                    {    //繼續獲取xe子節點的所有子節點
                        XmlNodeList nls = xe.ChildNodes;
                        for (int j = 0; j < nls.Count; j++)
                        {
                            XmlElement xe2 = (XmlElement)nls.Item(j);//轉換類型
                            //title、author、price都會在xe2.Name中取到
                            if (xe2.Name == "author")//如果找到
                            {
                                xe2.InnerText = "Karli Waston";//則修改
                            }
                            else //如果不存在則新建
                            {
                                xe2.SetAttribute("NewAttribute", "新增屬性");
                            }
                        }
                    }
                    else
                    {
                        //如果genre屬性值不為“李讚紅”，則修改為李讚紅
                        xe.SetAttribute("genre", "李讚紅");
                    }
                }
                else //如果不存在book節點，則在該節點下新增一個book下級節點
                {
                    XmlElement subElement = xmlDoc.CreateElement("因為這個節點不是book");
                    subElement.InnerXml = "BigDog";
                    xe.AppendChild(subElement);
                }
            }
            xmlDoc.Save("E:\\bookstore.xml");//保存。

<?xml version="1.0" encoding="gb2312"?>
<bookstore>
  <book genre="李讚紅" ISBN="2-3631-4">
    <title>CS從入門到精通</title>
    <author>候捷</author>
    <price>58.3</price>
  </book>
  <book genre="李讚紅" ISBN="2-3631-4">
    <title NewAttribute="新增屬性">CS從入門到精通</title>
    <author>Karli Waston</author>
    <price NewAttribute="新增屬性">58.3</price>
  </book>
  <book45 genre="李讚紅" ISBN="2-3631-4">
    <title>CS從入門到精通</title>
    <author>大黃</author>
    <price>58.3</price>
    <因為這個節點不是book>BigDog</因為這個節點不是book>
  </book45>
</bookstore>

XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load("E:\\bookstore.xml");
XmlNode root = xmlDoc.DocumentElement;
XmlElement subElement = xmlDoc.CreateElement("根節點下新增");
subElement.InnerXml = "BigDog";
root.AppendChild(subElement);