C++中异常处理问题的详细解析

#include <iOStream>
using namespace std;

int divide(int a, int b) {
    if (b == 0) {
        throw "Divisor can't be 0!";
    }
    return a / b;
}

int main() {
    int a, b;
    cout << "Enter two numbers: ";
    cin >> a >> b;
    try {
        int result = divide(a, b);
        cout << "Result: " << result << endl;
    } catch (const char* msg) {
        cout << "Error: " << msg << endl;
    }
    return 0;
}

#include <iostream>
using namespace std;

int divide(int a, int b) {
    if (b == 0) {
        throw "Divisor can't be 0!";
    }
    return a / b;
}

int main() {
    int a, b;
    cout << "Enter two numbers: ";
    cin >> a >> b;
    try {
        int result = divide(a, b);
        cout << "Result: " << result << endl;
        int* arr = new int[result];
        delete[] arr;  // 如果内存分配失败，将会抛出std::bad_alloc类型的异常
    } catch (const char* msg) {
        cout << "Error: " << msg << endl;
    } catch (std::bad_alloc& e) {
        cout << "Out of memory!" << endl;
    } catch (...) {
        cout << "Unknown error!" << endl;
    }
    return 0;
}

#include <iostream>
using namespace std;

void func1() {
    throw "Exception from func1!";
}

void func2() {
    try {
        func1();
    } catch (const char* msg) {
        cout << "Caught exception in func2: " << msg << endl;
        throw;  // 再抛出异常
    }
}

int main() {
    try {
        func2();
    } catch (const char* msg) {
        cout << "Caught exception in main: " << msg << endl;
    }
    return 0;
}

#include <iostream>
using namespace std;

class MyFile {
public:
    MyFile(string filename) {
        file.open(filename);
    }
    
    ~MyFile() {
        file.close();
    }
    
    void write(string content) {
        file << content;
        // 如果写入失败，将会抛出std::ios_base::failure类型的异常
        if (file.fail()) {
            throw std::ios_base::failure("Write failed!");
        }
    }
    
private:
    ofstream file;
};

int main() {
    try {
        MyFile myfile("test.txt");
        myfile.write("Hello, world!");
    } catch (std::ios_base::failure& e) {
        cout << "Write failed: " << e.what() << endl;
    }
    return 0;
}

#include <iostream>
#include <exception>
using namespace std;

class MyException : public exception {
public:
    const char* what() const throw() {
        return "My exception!";
    }
};

int main() {
    try {
        throw MyException();
    } catch (const exception& e) {
        cout << "Caught exception: " << e.what() << endl;
    }
    return 0;
}