示例

// cs0831.cs
using System;
using System.Linq;
using System.Linq.Expressions;

public class A
{
    public virtual int BaseMethod() { return 1; }
}
public class C : A
{
    public override int BaseMethod() { return 2; }
    public int Test(C c)
    {
        Expression<Func<int>> e = () => base.BaseMethod(); // CS0831

        // Try the following line instead, 
        // along with the BaseAccessHelper method.
        // Expression<Func<int>> e2 = () => BaseAccessHelper();
        return 1;
    } 
    // Uncomment to call from e2 expression above.
    // int BaseAccessHelper()
    // {
    //     return base.BaseMethod();
    // }
    
}