异常类型和异常变量的生命周期

throw的异常是有类型的，可以使，数字、字符串、类对象。

throw的异常是有类型的，catch严格按照类型进行匹配。

#define _CRT_SECURE_NO_WARNINGS
#include<iostream>


using namespace std;

class MyException {
public:

	MyException(){}
	//有参构造
	MyException(const char * str){
		mStr = new char[strlen(str) + 1];
		strcpy(mStr,str);
	}
	//拷贝构造
	MyException(const MyException & mE) {
		this -> mStr = new char[strlen(mE.mStr) + 1];
		strcpy(this->mStr,mE.mStr);
	}
	void what() {
		cout << mStr << endl;
	}

	~MyException() {
		if (mStr != NULL) {
			delete[] mStr;
		}
		cout << "对象析构" << endl;
	}
private:
	char * mStr;

};

void test01() {
	//创建一个匿名对象
	throw MyException("未知异常");
}

int main(char *argv[], int argc)
{
	try {
		test01();
	}
	catch (MyException mE) {
		mE.what();
	}
	return 0;
}

throw抛出去的如果是普通类型或者引用变量,它的生命周期是在catch结束后释放掉

如果throw抛出去的是一个指针,那么在进入catch前被释放掉

#define _CRT_SECURE_NO_WARNINGS
#include<iostream>


using namespace std;

class MyException {
public:

	MyException(){}
	//有参构造
	MyException(const char * str){
		cout << "对象构造" << endl;
		mStr = new char[strlen(str) + 1];
		strcpy(mStr,str);
	}
	//拷贝构造
	MyException(const MyException & mE) {
		this -> mStr = new char[strlen(mE.mStr) + 1];
		strcpy(this->mStr,mE.mStr);
	}
	void what() {
		cout << mStr << endl;
	}

	~MyException() {
		if (mStr != NULL) {
			delete[] mStr;
		}
		cout << "对象析构" << endl;


	}
private:
	char * mStr;

};

void test01() {
	//创建一个匿名对象,如果抛出的是指针,会在进入catch前就释放掉该指针
	cout << "&(MyException(未知异常))" << endl;
	throw &(MyException("未知异常"));
}
void test02() {
	//创建一个匿名对象,抛出一个普通对象,用引用去接

	cout << "MyException(未知异常)" << endl;
	throw MyException("未知异常");
}

void test03() {

	//创建一个匿名对象,抛出一个普通对象
	cout << "MyException(未知异常) 用普通对象来接" << endl;
	throw MyException("未知异常");
}

int main(char *argv[], int argc)
{
	try {
		test01();

	}
	
	catch (MyException * mE) {
		cout << "未知异常" << endl;
	
	}

	cout << "=================================" << endl;

	try {
		test02();
	}
	catch (MyException & mE)
	{
		cout << "未知异常" << endl;

	}

	cout << "=================================" << endl;


	try {
		test03();
	}
	catch (MyException  mE)
	{
		cout << "未知异常" << endl;

	}
	return 0;
}