Question

我想将一个元素添加到XML文件中，条件为：

like where attribute("id").value=="1"

在此代码中，where子句不起作用：

string xmlFilePath = MapPath("Employees.xml");
XDocument xmlDoc = XDocument.Load(xmlFilePath);
try
{
    xmlDoc.Element("employees").Element("employee")
        .Where(employee => employee.Attribute("id").Value == "2").FirstOrDefault())
        .Add(new XElement("city", "welcome"));

    xmlDoc.Save(xmlFilePath);
}
catch (XmlException ex)
{
    //throw new XmlException
}

Answer 1

这可能会更好：

XDocument xmlDoc = XDocument.Load(xmlFilePath);
try
{
    xmlDoc
        // get the employees element
        .Element("employees")
        // get all the employee elements
        .Elements("employee")
        // but filter down to the first one that has id == 2
        .Where(employee => employee.Attribute("id").Value == "2").FirstOrDefault()
        // and add a new city element to it
        .Add(new XElement("city", "welcome"));
    // save the document
    xmlDoc.Save("D:\\x.xml");
}
catch (XmlException ex)
{
    //throw new XmlException
}

带有属性（“id”）的where子句的LINQ to XML查询.value ==“1”

1 个答案: