传递的时候尽量传引用

#include <iostream>
#include "TestClass.h"
using namespace std;
TestClass test(){
    TestClass t;
    return t;
}
void test1(TestClass testClass){
    cout << "对象作为参数传递" << endl;
}
void test2(TestClass &testClass){
    cout << "引用作为参数传递" << endl;
    cout << "最好传引用" << endl;
    cout << "如果担心值被改变，那就加上const，有成员函数是用不了，就把要调用的函数加上const" << endl;
}
int main(){
    TestClass t1 = test();
    cout << "开始调用" << endl;
    test1(t1);
    test2(t1);
    system("pause");
    return 0;
}

#pragma once
class TestClass
{
public:
    TestClass();
    TestClass(const TestClass &testClass);
    ~TestClass();
};

#include "TestClass.h"
#include <iostream>
using namespace std;
TestClass::TestClass()
{
    cout << "testClass" << endl;
}
TestClass::TestClass(const TestClass &testClass){
    cout << "copy constructor" << endl;
}
TestClass::~TestClass()
{
    cout << "destructor" << endl;
}