如何小弟我定义operator ==后,使用一直报错

怎么我定义operator ==后,使用一直报错?
我定义了
public static bool operator ==(MyShape lhs, object rhs).....
public static bool operator !=(MyShape lhs, object rhs).....

编译没有问题,怎么一和NULL比较就报错?
MyShape shape1 = null;
...
if (shape1 == null)...

[解决办法]

C# code

public static bool operator ==(MyShape lhs, object rhs){   if( object.ReferenceEqual(lhs, rhs) ) return true;   if( object.ReferenceEqual(lhs,null) || object.ReferenceEqual(rhs,null) ) return false;   ...}public static bool operator !=(MyShape lhs, object rhs){   return !(lhs == rhs);}