c#这段代码怎么理解，谢谢

Question

public class JZD
{
    public string JZDHANDLE;
    public string JZDBSM;
    public string JZDYSDM;
    public JZD()
    {
        JZDHANDLE = "";
        JZDBSM = "";
        JZDYSDM = "";
    }
    public string retrunVal(string ZDMC)
    {
        switch (ZDMC)
        {
            case "JZDHANDLE": return JZDHANDLE;
            case "JZDBSM": return JZDBSM;
            case "JZDYSDM": return JZDYSDM;
            default: return "";
        }
    }
}

Answer 1

不过定义了一个类，几个成员变量，然后一个构造函数而已，
核心方法只有下面这个，根据输入字符串，返回不同的成员变量

public string retrunVal(string ZDMC)
    {
        switch (ZDMC)
        {
            case "JZDHANDLE": return JZDHANDLE;
            case "JZDBSM": return JZDBSM;
            case "JZDYSDM": return JZDYSDM;
            default: return "";
        }
    }