已知有一个XML文件（bookstore.xml）如下： <?xml version="1.0" encoding="gb2312"?> <bookstore> <book genre="fantasy" ISBN="2-3631-4"> <title>Oberon's Legacy</title> <author>Corets,Eva</author> <price>5.95</price> </book> </bookstore> 1、往<bookstore>节点中插入一个<book>节点： Dim xmlDoc As New XmlDocument()xmlDoc.Load("bookstore.xml")Dim root As XmlNode = xmlDoc.SelectSingleNode("bookstore") '查找<bookstore> Dim xe1 As XmlElement = xmlDoc.CreateElement("book") '创建一个<book>节点 xe1.SetAttribute("genre","李赞红") '设置该节点genre属性 xe1.SetAttribute("ISBN","2-3631-4") '设置该节点ISBN属性 Dim xesub1 As XmlElement = xmlDoc.CreateElement("title")xesub1.InnerText = "CS从入门到精通" '设置文本节点 xe1.AppendChild(xesub1) '添加到<book>节点中 Dim xesub2 As XmlElement = xmlDoc.CreateElement("author")xesub2.InnerText = "候捷"xe1.AppendChild(xesub2)Dim xesub3 As XmlElement = xmlDoc.CreateElement("price")xesub3.InnerText = "58.3"xe1.AppendChild(xesub3)root.AppendChild(xe1) '添加到<bookstore>节点中 xmlDoc.Save("bookstore.xml")//=============================================== 结果为： <?xml version="1.0" encoding="gb2312"?> <bookstore> <book genre="fantasy" ISBN="2-3631-4"> <title>Oberon's Legacy</title> <author>Corets,Eva</author> <price>5.95</price> </book> <book genre="李赞红" ISBN="2-3631-4"> <title>CS从入门到精通</title> <author>候捷</author> <price>58.3</price> </book> </bookstore> 2、修改节点：将genre属性值为“李赞红“的节点的genre值改为“update李赞红”，将该节点的子节点<author>的文本修改为“亚胜”。 Dim nodeList As XmlNodeList = xmlDoc.SelectSingleNode("bookstore").ChildNodes '获取bookstore节点的所有子节点 Dim xn As XmlNodeFor Each xn In nodeList '遍历所有子节点 Dim xe As XmlElement = CType(xn,XmlElement) '将子节点类型转换为XmlElement类型 If xe.GetAttribute("genre") = "李赞红" Then '如果genre属性值为“李赞红” xe.SetAttribute("genre","update李赞红") '则修改该属性为“update李赞红” Dim nls As XmlNodeList = xe.ChildNodes '继续获取xe子节点的所有子节点 Dim xn1 As XmlNodeFor Each xn1 In nls '遍历 Dim xe2 As XmlElement = CType(xn1,XmlElement) '转换类型 If xe2.Name = "author" Then '如果找到 xe2.InnerText = "亚胜" '则修改 Exit ForEach '找到退出来就可以了 End IfNext xn1Exit ForEachEnd IfNext xnxmlDoc.Save("bookstore.xml") '保存。 //================================================== 最后结果为： <?xml version="1.0" encoding="gb2312"?> <bookstore> <book genre="fantasy" ISBN="2-3631-4"> <title>Oberon's Legacy</title> <author>Corets,Eva</author> <price>5.95</price> </book> <book genre="update李赞红" ISBN="2-3631-4"> <title>CS从入门到精通</title> <author>亚胜</author> <price>58.3</price> </book> </bookstore> 3、删除 <book genre="fantasy" ISBN="2-3631-4">节点的genre属性，删除 <book genre="update李赞红" ISBN="2-3631-4">节点。 Dim xnl As XmlNodeList = xmlDoc.SelectSingleNode("bookstore").ChildNodesDim xn As XmlNodeFor Each xn In xnlDim xe As XmlElement = CType(xn,XmlElement)If xe.GetAttribute("genre") = "fantasy" Thenxe.RemoveAttribute("genre") '删除genre属性 ElseIf xe.GetAttribute("genre") = "update李赞红" Thenxe.RemoveAll() '删除该节点的全部内容 End IfEnd IfNext xnxmlDoc.Save("bookstore.xml")//=========================================== 最后结果为： <?xml version="1.0" encoding="gb2312"?> <bookstore> <book ISBN="2-3631-4"> <title>Oberon's Legacy</title> <author>Corets,Eva</author> <price>5.95</price> </book> <book> </book> </bookstore> 4、显示所有数据。 Dim xn As XmlNode = xmlDoc.SelectSingleNode("bookstore")Dim xnl As XmlNodeList = xn.ChildNodesDim xnf As XmlNodeFor Each xnf In xnlDim xe As XmlElement = CType(xnf,XmlElement)Console.WriteLine(xe.GetAttribute("genre")) '显示属性值 Console.WriteLine(xe.GetAttribute("ISBN"))Dim xnf1 As XmlNodeList = xe.ChildNodesDim xn2 As XmlNodeFor Each xn2 In xnf1Console.WriteLine(xn2.InnerText) '显示子节点点文本 Next xn2Next xnf
