关于这个问题从调用方法中获取参数名称 https://stackoverflow.com/questions/15205457/get-the-name-of-parameters-from-a-calling-method and 在 C# 中查找传递给函数的变量名 https://stackoverflow.com/questions/72121/finding-the-variable-name-passed-to-a-function-in-c-sharp我仍在寻找一种方法来定义WhatDoesTheAnimalSay_WANTED方法：我想知道用作参数的变量的名称：
public class Farm
{
public readonly string Cow = "Muuuuhh";
public string Cat { get; set; }
public void MainFunction()
{
var dog = "WauWau";
var kiwi = new Bird("QueeeekQueeek");
Cat = "Miiiaaauuuu";
// This one works but looks kinda ugly and is cumbersome when used
WhatDoesTheAnimalSay(nameof(dog), dog);
WhatDoesTheAnimalSay(nameof(Cow), Cow);
WhatDoesTheAnimalSay(nameof(Cat), Cat);
WhatDoesTheAnimalSay(nameof(kiwi), kiwi);
WhatDoesTheAnimalSay_WRONG1(dog);
WhatDoesTheAnimalSay_WRONG2(dog);
WhatDoesTheAnimalSay_WANTED(dog);
WhatDoesTheAnimalSay_WANTED(Cow);
}
public void WhatDoesTheAnimalSay<T>(string name, T says)
{
MessageBox.Show("The " + name + " says: " + says);
// Shows i.e.: The dog says: WauWau
}
public void WhatDoesTheAnimalSay_WRONG1<T>(T says)
{
MessageBox.Show("The " + nameof(says) + " says: " + says);
// Shows: The says says: WauWau
}
public void WhatDoesTheAnimalSay_WRONG2<T>(T says, [CallerMemberName] string name = null)
{
MessageBox.Show("The " + name + " says: " + says);
// Shows: The MainFunction says: WauWau
}
public void WhatDoesTheAnimalSay_WANTED<T>(T says /*, ?????*/)
{
MessageBox.Show("The " /*+ ?????*/ + " says: " + says);
// Shows: The dog says: WauWau
}
}
// Just here to show it should work with a class as well.
public class Bird
{
public string Says { get; } //readonly
public Bird(string says) {
Says = says;
}
public override string ToString()
{
return Says;
}
}
在现实生活中，我在实施时需要这个IXmlSerializable我的类中带有自定义接口reader.Read... and writer.Write....方法。
所以，不幸的是，我cannot介绍一个新的包装类、接口或者更改动物名称或其内容的保存位置。这意味着它必须与类和纯字符串、整数、小数...变量、字段或属性以及。
换句话说（不是以粗鲁的方式）：不要改变动物的定义方式，只需改变WhatDoesTheAnimalSay_WANTED方法...
EDIT:
由于你们中的一些人想了解此示例的真实用例，因此我在这里向您介绍如何在 xml 文件中存储和读取数据。真正的数据库对象当然要大得多，并且所有子类（例如Fitter）实施IXmlSerializable接口以及使用相同的扩展方法。
// This is the Database Class which stores all the data
public class Database : IXmlSerializable
{
// The list of all building sites managed
public List<BuildingSite> BuildingSites { get; set; }
// The list of all fitters working for the company
public List<Fitter> Fitters { get; set; }
private readonly int DatabaseVersion = 1;
// Write implementation of the IXmlSerializable inteface
public void WriteXml(XmlWriter writer)
{
// Writing all Data into the xml-file
writer.WriteElementInt(nameof(DatabaseVersion), DatabaseVersion);
writer.WriteElementList(nameof(BuildingSites), BuildingSites);
writer.WriteElementList(nameof(Fitters), Fitters);
}
public void ReadXml(XmlReader reader)
{
// Do the reading here
}
public XmlSchema GetSchema() { return null; }
}
public class XmlExtensions
{
// Writing a list into the xml-file
public static void WriteElementList<T>(this XmlWriter writer, string elementName, IEnumerable<T> items)
{
var list = items is List<T> ? items : items.ToList();
// The XML-Element should have the name of the variable in Database!!!
writer.WriteStartElement(elementName);
writer.WriteAttributeString("count", list.Count().ToString());
var serializer = new XmlSerializer(typeof(T));
list.ForEach(o => serializer.Serialize(writer, o, XmlHelper.XmlNamespaces));
writer.WriteEndElement();
}
public static void WriteElementInt(this XmlWriter writer, string elementName, int toWrite)
{
// The XMLElement should have the name of the variable in Database!!!
writer.WriteElementString(elementName, toWrite.ToString(CultureInfo.InvariantCulture));
}
// More here....
}
}
