将字符串映射到c＃中的方法调用

Question

假设有这些类：

class A    
{    
    public string someField="something";        
    public void MethodA(){}     
}

class B
{
    public A propertyA;
}

class C
{
    public B propertyB;
    string s1 = "propertyB.propertyA.MethodA()";        
    string s2 = "propertyB.propertyA.someField";
    public void Method()
    {
        //so for s1 it does
        propertyB.propertyA.MethodA();
        //and for s2 it does
        var something = propertyB.propertyA.someField;
        //or
        propertyB.propertyA.someField = "somethingNew"
    }
}

如何在类C中执行A类中的方法，表示为字符串s1并获取或赋值给someField（s2）？