1、 认识xml
可扩展标记语言，一种用于标记电子文档使其具有结果性的标记语言，它可以用来标记数据、定义数据类型，是一种允许用户对自己的标记语言进行定义的源语言。
2、 和超文本标记语言区别
2.1 html不一定需要成对出现，xml则一定需要成对出现。
2.2 html 不区分大小写，但是xml区分。
3、对xml文档增删改查
//声明一个XmlDocument空对象
protected XmlDocument XmlDoc = new XmlDocument();
/// <summary>
/// 构造函数，导入xml文件
/// </summary>
/// <param name="path"></param>
public XmlHelper(string path)
{
try
{
XmlDoc.Load(path);
}
catch (Exception ex)
{
throw ex;
}
}
/// <summary>
/// 保存文件
/// </summary>
/// <param name="path"></param>
public void SaveXml(string path)
{
try
{
XmlDoc.Save(path);
}
catch (System.Exception ex)
{
throw ex;
}
}
/// <summary>
/// 获取节点的子节点的内容
/// </summary>
/// <param name="path"></param>
/// <param name="rootNode"></param>
/// <param name="attributeName"></param>
/// <returns></returns>
public string GetNodeChildAttribute(string path, string rootNode, string attributeName)
{
XmlNode xn = XmlDoc.SelectSingleNode(rootNode);
StringBuilder sb = new StringBuilder();
XmlNodeList xnl = xn.ChildNodes; foreach (XmlNode xnf in xnl)
{
XmlElement xe = (XmlElement)xnf;
XmlNodeList xnf1 = xe.ChildNodes;
foreach (XmlNode xn2 in xnf1)
{
if (xn2.Name == attributeName)
{
sb.Append(xn2.InnerText);//显示子节点点文本
}
}
}
return sb.ToString();
}
/// <summary>
/// 获取节点的属性值
/// </summary>
/// <param name="path">xml路径</param>
/// <param name="rootNode">根节点名称</param>
/// <param name="attributeName">属性名称</param>
/// <returns></returns>
public string GetNodeAttribute(string path, string rootNode, string attributeName)
{
try
{
XmlNode xn = XmlDoc.SelectSingleNode(rootNode);
XmlNodeList xnl = xn.ChildNodes;
StringBuilder sb = new StringBuilder();
foreach (XmlNode xnf in xnl)
{
XmlElement xe = (XmlElement)xnf;
sb.Append(xe.GetAttribute(attributeName));
}
return sb.ToString();
}
catch (Exception)
{ throw;
}
}
/// <summary>
/// 删除节点/节点属性
/// </summary>
/// <param name="path">xml文件地址</param>
/// <param name="rootNode">根节点名称</param>
/// <param name="delNode">要删除的节点</param>
/// <param name="attributeName">节点属性</param>
/// <param name="attributeValue">属性值</param>
public void DeleteNode(string path, string rootNode, string attributeName, string attributeValue)
{
try
{
XmlNodeList xnl = XmlDoc.SelectSingleNode(rootNode).ChildNodes;
foreach (XmlNode xn in xnl)
{
XmlElement xe = (XmlElement)xn;
if (xe.GetAttribute(attributeName) == attributeValue)
{
//xe.RemoveAttribute(attributeName);//删除属性
xe.RemoveAll();//删除该节点的全部内容
}
}
SaveXml(path);
}
catch (Exception)
{ throw;
}
}
/// <summary>
/// 修改节点的子节点内容
/// </summary>
/// <param name="path">xml文件路径</param>
/// <param name="rootNode">根节点名称</param>
/// <param name="attributeName">节点的子节点名称</param>
/// <param name="attributeOldValue">节点的子节点原始内容</param>
/// <param name="attributeNewValue">节点的子节点新内容</param>
public void UpdateChildNodeAttribute(string path, string rootNode, string attributeName, string attributeOldValue, string attributeNewValue)
{
try
{
XmlNodeList nodeList = XmlDoc.SelectSingleNode(rootNode).ChildNodes;//获取根节点的所有子节点
foreach (XmlNode xn in nodeList)//遍历所有子节点
{
XmlElement xe = (XmlElement)xn;//将子节点类型转换为XmlElement类型
if (string.IsNullOrEmpty(attributeName) || string.IsNullOrEmpty(attributeOldValue))
{
return;
}
else
{
XmlNodeList nls = xe.ChildNodes;
if (nls != null && nls.Count > )
{
foreach (XmlNode xn1 in nls)//遍历
{
XmlElement xe2 = (XmlElement)xn1;//转换类型
if (xe2.InnerText == attributeOldValue)//如果找到
{
xe2.InnerText = attributeNewValue;//则修改
break;//找到退出来就可以了
}
}
}
}
}
SaveXml(path);
}
catch (Exception)
{ throw;
}
}
/// <summary>
/// 修改节点属性值操作
/// </summary>
/// <param name="path">xml文件路径</param>
/// <param name="rootNode">根节点名称，如：bookstore</param>
/// <param name="attributeName">节点属性名</param>
/// <param name="attributeOldValue">节点属性原来值</param>
/// <param name="attributeNewValue">节点属性修改后的值</param>
public void UpdateNodeAttribute(string path, string rootNode, string attributeName, string attributeOldValue, string attributeNewValue)
{
try
{
XmlNodeList nodeList = XmlDoc.SelectSingleNode(rootNode).ChildNodes;//获取根节点的所有子节点
foreach (XmlNode xn in nodeList)//遍历所有子节点
{
XmlElement xe = (XmlElement)xn;//将子节点类型专程xmlelement类型
if (string.IsNullOrEmpty(attributeName) || string.IsNullOrEmpty(attributeOldValue))
{
return;
}
else
{
if (xe.GetAttribute(attributeName) == attributeOldValue)
{
xe.SetAttribute(attributeName, attributeNewValue);
}
}
}
SaveXml(path);
}
catch (Exception)
{ throw;
}
}
/// <summary>
/// 插入节点操作
/// </summary>
/// <param name="path">xml文件路径</param>
/// <param name="rootNode">根节点名称，如：bookstore</param>
/// <param name="node">节点名称，如：book</param>
/// <param name="nodeAttributes">节点的属性-属性值集合</param>
/// <param name="childAttributes">节点子节点名称-内容</param>
public void InsertNode(string path, string rootNode, string node, Dictionary<string, string> nodeAttributes, Dictionary<string, string> childAttributes)
{
try
{
XmlNode root = XmlDoc.SelectSingleNode(rootNode);//找到根节点bookstore
XmlElement xe1 = XmlDoc.CreateElement(node);//创建子节点book
if (nodeAttributes != null && nodeAttributes.Count > )
{
foreach (var n in nodeAttributes)
{
xe1.SetAttribute(n.Key, n.Value);
}
}
if (childAttributes != null && childAttributes.Count > )
{
XmlElement xesub1;
foreach (var n in childAttributes)
{
xesub1 = XmlDoc.CreateElement(n.Key);
xesub1.InnerText = n.Value;
xe1.AppendChild(xesub1);//添加到<book>节点中
}
}
root.AppendChild(xe1);
SaveXml(path);
}
catch (Exception)
{ throw;
}
}
调用：
string path = Server.MapPath("Books.xml");
XmlHelper xHelper = new XmlHelper(path);
/*插入*/
//Dictionary<string, string> dc1 = new Dictionary<string, string>();
//dc1.Add("genre", "李赞红");
//dc1.Add("ISBN", "2-3631-4");
//Dictionary<strin插入g, string> dc2 = new Dictionary<string, string>();
//dc2.Add("title", "CS从入门到精通");
//dc2.Add("author", "候捷");
//dc2.Add("price", "58.3");
//xHelper.InsertNode(path, "bookstore", "book", dc1, dc2);
/*修改*/
//xHelper.UpdateNodeAttribute(path, "bookstore", "genre", "李赞红", "李");
//xHelper.UpdateChildNodeAttribute(path, "bookstore", "title", "CS从入门到精通", "cs");
/*删除节点*/
//xHelper.DeleteNode(path, "bookstore", "genre", "李");
//Response.Write(xHelper.GetNodeAttribute(path, "bookstore", "genre"));
//Response.Write(xHelper.GetNodeChildAttribute(path, "bookstore", "price"));
4、通过xml数据绑定
xml转DataTable
public DataTable XmlToData(string path, string rootNode, params string[] columns)
{
DataTable dt = new DataTable();
XmlNodeList xn = XmlDoc.SelectSingleNode(rootNode).ChildNodes;
try
{
if (columns.Length > )
{
DataColumn dc;
for (int i = ; i < columns.Length; i++)
{
dc = new DataColumn(columns[i]);
dt.Columns.Add(dc);
}
foreach (XmlNode xnf in xn)
{
XmlElement xe = (XmlElement)xnf;
XmlNodeList xnf1 = xe.ChildNodes;
int i = ;
DataRow dr = dt.NewRow();
foreach (XmlNode xn2 in xnf1)
{
dr[i] = xn2.InnerText;
i++;
}
dt.Rows.Add(dr);
}
}
}
catch (Exception)
{ throw;
}
return dt; }
调用：
//string[] arr = { "title", "author", "price" };
//GridView1.DataSource = xHelper.XmlToData(path, "bookstore", arr);
//GridView1.DataBind();
DataTable转xml
/*datatable转xml*/
public string DataTableToXml(DataTable dt)
{
if (dt != null)
{
MemoryStream ms = null;
XmlTextWriter XmlWt = null;
try
{
ms = new MemoryStream();
//根据ms实例化XmlWt
XmlWt = new XmlTextWriter(ms, Encoding.Unicode);
//获取ds中的数据
dt.WriteXml(XmlWt);
int count = (int)ms.Length;
byte[] temp = new byte[count];
ms.Seek(, SeekOrigin.Begin);
ms.Read(temp, , count);
//返回Unicode编码的文本
UnicodeEncoding ucode = new UnicodeEncoding();
string returnValue = ucode.GetString(temp).Trim();
return returnValue;
}
catch (System.Exception ex)
{
throw ex;
}
finally
{
//释放资源
if (XmlWt != null)
{
XmlWt.Close();
ms.Close();
ms.Dispose();
}
}
}
else
{
return "";
}
}
调用：
//bool s = xHelper.CDataToXmlFile(xHelper.XmlToData(path, "bookstore", arr), "Bookss.xml","book");
5、xml序列化反序列化
[Serializable]
public class Person
{
public string Name { get; set; }
public int Age { get; set; }
}
public class CXmlSerializer<T> where T : new()
{
private static XmlSerializer _Serializer = new XmlSerializer(typeof(T)); public static string Serialize(T t)
{
string s = "";
using (MemoryStream ms = new MemoryStream())
{
_Serializer.Serialize(ms, t);
s = System.Text.UTF8Encoding.UTF8.GetString(ms.ToArray());
}
return s;
} public static T Deserialize(string s)
{
T t;
using (MemoryStream ms = new MemoryStream(System.Text.Encoding.UTF8.GetBytes(s)))
{
t = (T)_Serializer.Deserialize(ms);
}
return t;
}
}
调用：
List<Person> list = new List<Person> { new Person { Name = "Xuj", Age = }, new Person { Name = "duj", Age = }, new Person { Name = "fuj", Age = } };
string s = CXmlSerializer<List<Person>>.Serialize(list);