写一个C++程序代码，能够在文件中对在代码运行界面输入的会员信息进行增删改查。

以下是一个简单的 C++ 代码示例，可以实现会员信息的增删改查功能。该程序将会员信息保存在一个文件中，每行代表一个会员的信息，包括会员编号、姓名、电话号码和地址。

#include <iostream>
#include <fstream>
#include <string>
using namespace std;

struct Member {
    string id;
    string name;
    string phone;
    string address;
};

void addMember(ofstream& fout, Member& member) {
    fout << member.id << ' ' << member.name << ' ' << member.phone << ' ' << member.address << endl;
    cout << "Member added successfully." << endl;
}

void deleteMember(ifstream& fin, ofstream& fout, const string& id) {
    Member member;
    bool found = false;
    while (fin >> member.id >> member.name >> member.phone >> member.address) {
        if (member.id == id) {
            found = true;
            continue;
        }
        fout << member.id << ' ' << member.name << ' ' << member.phone << ' ' << member.address << endl;
    }
    if (found) {
        cout << "Member deleted successfully." << endl;
    } else {
        cout << "Member not found." << endl;
    }
}

void updateMember(ifstream& fin, ofstream& fout, const string& id, Member& member) {
    Member oldMember;
    bool found = false;
    while (fin >> oldMember.id >> oldMember.name >> oldMember.phone >> oldMember.address) {
        if (oldMember.id == id) {
            found = true;
            oldMember = member;
        }
        fout << oldMember.id << ' ' << oldMember.name << ' ' << oldMember.phone << ' ' << oldMember.address << endl;
    }
    if (found) {
        cout << "Member updated successfully." << endl;
    } else {
        cout << "Member not found." << endl;
    }
}

void searchMember(ifstream& fin, const string& id) {
    Member member;
    bool found = false;
    while (fin >> member.id >> member.name >> member.phone >> member.address) {
        if (member.id == id) {
            found = true;
            cout << "ID: " << member.id << endl;
            cout << "Name: " << member.name << endl;
            cout << "Phone: " << member.phone << endl;
            cout << "Address: " << member.address << endl;
            break;
        }
    }
    if (!found) {
        cout << "Member not found." << endl;
    }
}

int main() {
    ofstream fout("members.txt", ios::app);
    ifstream fin("members.txt");
    if (!fout || !fin) {
        cout << "Error opening file." << endl;
        return 1;
    }
    while (true) {
        cout << "1. Add member" << endl;
        cout << "2. Delete member" << endl;
        cout << "3. Update member" << endl;
        cout << "4. Search member" << endl;
        cout << "5. Exit" << endl;
        int choice;
        cout << "Enter your choice: ";
        cin >> choice;
        switch (choice) {
        case 1:
            {
                Member member;
                cout << "Enter member ID: ";
                cin >> member.id;
                cout << "Enter member name: ";
                cin >> member.name;
                cout << "Enter member phone: ";
                cin >> member.phone;
                cout << "Enter member address: ";
                cin >> member.address;
                addMember(fout, member);
                break;
            }
        case 2:
            {
                string id;
                cout << "Enter member ID to delete: ";
                cin >> id;
                deleteMember(fin, fout, id);
                break;
            }
        case 3:
            {
                string id;
                cout << "Enter member ID to update: ";
                cin >> id;
                Member member;
                cout << "Enter member name: ";
                cin >> member.name;
                cout << "Enter member phone: ";
                cin >> member.phone;
                cout << "Enter member address: ";
                cin >> member.address;
                updateMember(fin, fout, id, member);
                break;
            }
        case 4:
            {
                string id;
                cout << "Enter member ID to search: ";
                cin >> id;
                searchMember(fin, id);
                break;
            }
        case 5:
            return 0;
        default:
            cout << "Invalid choice." << endl;
        }
    }
    fout.close();
    fin.close();
    return 0;
}

注意，该代码并没有对输入进行很好的错误处理，生产环境下需要更严格的输入验证和异常处理。