在构造函数中使用默认对象参数

在构造函数中使用默认对象参数我想在构造函数中使用默认参数植，但是其中有一个参数是另一个类的对象，如下：MyClass::MyClass(int size = 3, int xD = 0,int yD = 0, Point head = Point(20,20) ){ //．．．函数实现}我应该怎么样写才正确呢？请问以上对吗？对ok啊对的呀这是我做的#include <iostream>using namespace std;class A{private: int FValue;public: A(){} A(int x){ FValue = x; } getValue(){ return FValue; } assign(A &a) { FValue = a.FValue; }};class Test{private: int FValue; A FA;public: Test(A a); int getValue() { return FA.getValue(); }};Test::Test(A a = A(10)){ FA.assign( a );}int main(int argc, char* argv[]){ Test *testgroup = new Test(); cout << testgroup->getValue() << endl; int i; cin >> i;}#include <iostream>using namespace std;class A{private: int FValue;public: A(){} A(int x){ FValue = x; } getValue(){ return FValue; } assign(A &a) { FValue = a.FValue; }};class Test{private: int FValue; A FA;public: Test(A a); int getValue() { return FA.getValue(); }};Test::Test(A a = A(10)){ FA.assign( a );}int main(int argc, char* argv[]){ Test *testgroup = new Test(); cout << testgroup->getValue() << endl; int i; cin >> i;}楼主对的,默认参数植可以是表达式.ok