如果：XElement存在，否则创建新的

我的XML文件：

   0 0   

首先，我需要检查xml .element("player").attribute("name")是否存在用户名“Tardis”。

如果没有，我需要创建它，杀戮和死亡为零。 如果确实如此，我需要阅读杀戮和死亡并将它们设置为变量。

我一直在使用XElement尝试这样做..谢谢！

用于编写XML的代码：

 public static string username = "Tardis"; public static int kills = 0; public static int deaths = 0; ........ XElement Players = new XElement( "SimpleKD", new XElement("player", new XAttribute("name", username), new XElement("kills", kills), new XElement("deaths", deaths))); 

Answer 1

假设你有一个Player类：

 private static Player GetPlayer(string name, XElement simpleKD) { var playerElem = simpleKD.Elements("player") .SingleOrDefault(p => p.Attribute("name").Value == name); if (playerElem == null) { simpleKD.Add(new XElement("player", new XAttribute("name", name), new XElement("kills", 0), new XElement("deaths", 0))); return new Player(name); } return new Player(name, (int)playerElem.Element("kills"), (int)playerElem.Element("deaths")); } 

Answer 2

 XmlDocument xmlfile= new XmlDocument(); xmlfile.Load("FileName.xml"); XmlNode node = xmlfile.SelectSingleNode("//SimpleKD"); XmlElement element = (XmlElement)node.SelectSingleNode(string.Format("//player[@name='{0}']", "Tardis")); if(element == null) { element = node.CreateElement("player"); element .SetAttribute("name", "Tardis"); node.AppendChild(element); xmlfile.Save("FileName.xml"); XmlElement newElement = new Element(); newElement = node.CreateElement("Kills"); newElement.Value = 0; element.AppendChild(newElement); newElement = node.CreateElement("Deaths"); newElement.Value = 0; element.AppendChild(newElement); xmlfile.Save("FileName.xml"); } else { kills = element.FirstChild.Value; deaths = element.LastChild.Value; } 

Answer 3

  int k = 0, d = 0; //kills and deaths var doc = XDocument.Parse(xmlString); var elem = doc.XPathSelectElement("/SimpleKD/player[@name='Tardis']"); if (elem != null) { var killsNode = (XElement)elem.FirstNode; k = (int)killsNode; var deathsNode = (XElement)killsNode.NextNode; d = (int)deathsNode; } else { elem = doc.XPathSelectElement("/SimpleKD"); elem.Add(new XElement("player", new XAttribute("name", "Tardis"), new XElement("kills", k), new XElement("deaths", d))); } xmlString = doc.ToString(); Console.WriteLine("Kills: {0}", k); Console.WriteLine("Deaths: {0}", d); 

Answer 4

如果播放器位于xml的任何部分，则使用simpleKD.Descendants。 如果它作为直接子项存在，则使用simpleKD.Elements

  private Player GetPlayer(string name, XElement simpleKD) { var playerElem = simpleKD.Descendants("player").SingleOrDefault(x => x.Attribute("name").Value.Equals(name)); if (playerElem == null) { simpleKD.Add(new XElement("player", new XAttribute("name", name), new XElement("kills", 0), new XElement("deaths", 0))); return new Player(name); } return new Player(name, (int)playerElem.Element("kills"), (int)playerElem.Element("deaths")); } class Player { public string Kills { get; set; } public string Deaths { get; set; } public Player() { } public Player(string name) { } public Player(string name, int kills, int deaths) { } }