C#将XML解析为列表返回空列表

using System;
using System.Collections.Generic;
using System.Xml;

public class XmlParser
{
    public List<string> ParseXmlToList(string xml)
    {
        List<string> resultList = new List<string>();

        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.LoadXml(xml);

        XmlNodeList nodeList = xmlDoc.SelectNodes("//item");
        foreach (XmlNode node in nodeList)
        {
            resultList.Add(node.InnerText);
        }

        return resultList;
    }
}