用C语言TCP套接字编写关于员工管理系统的输入、修改、浏览、查询、删除员工信息功能服务端的具体代码

以下是一个简单的员工管理系统服务端的代码示例，包括输入、修改、浏览、查询和删除员工信息的功能。本示例使用 TCP 套接字进行通信，使用了 MySQL 数据库进行数据存储。

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <mysql/mysql.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <unistd.h>

#define MAX_BUFFER_SIZE 1024
#define PORT 8888

void error_handling(const char *message);
void handle_input(int client_sock, MYSQL *conn);
void handle_view(int client_sock, MYSQL *conn);
void handle_modify(int client_sock, MYSQL *conn);
void handle_search(int client_sock, MYSQL *conn);
void handle_delete(int client_sock, MYSQL *conn);

int main(int argc, char *argv[])
{
    int serv_sock, client_sock;
    struct sockaddr_in serv_addr, client_addr;
    socklen_t client_addr_size;

    // 初始化 MySQL 连接
    MYSQL *conn = mysql_init(NULL);
    if (!conn)
    {
        fprintf(stderr, "mysql_init() failed\n");
        exit(1);
    }

    // 连接到 MySQL 数据库
    if (!mysql_real_connect(conn, "localhost", "root", "password", "employee", 0, NULL, 0))
    {
        fprintf(stderr, "%s\n", mysql_error(conn));
        mysql_close(conn);
        exit(1);
    }

    // 创建套接字
    serv_sock = socket(PF_INET, SOCK_STREAM, 0);
    if (serv_sock == -1)
        error_handling("socket() error");

    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(PORT);

    // 绑定套接字
    if (bind(serv_sock, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) == -1)
        error_handling("bind() error");

    // 监听套接字
    if (listen(serv_sock, 5) == -1)
        error_handling("listen() error");

    // 接受客户端请求
    while (1)
    {
        client_addr_size = sizeof(client_addr);
        client_sock = accept(serv_sock, (struct sockaddr *)&client_addr, &client_addr_size);
        if (client_sock == -1)
            error_handling("accept() error");

        printf("Connected client IP : %s\n", inet_ntoa(client_addr.sin_addr));
        handle_input(client_sock, conn);
        close(client_sock);
    }

    mysql_close(conn);
    return 0;
}

void error_handling(const char *message)
{
    fputs(message, stderr);
    fputc('\n', stderr);
    exit(1);
}

void handle_input(int client_sock, MYSQL *conn)
{
    char buffer[MAX_BUFFER_SIZE];
    int str_len;

    while ((str_len = read(client_sock, buffer, MAX_BUFFER_SIZE)) != 0)
    {
        buffer[str_len] = 0;
        printf("Received message from client : %s\n", buffer);

        if (strncmp(buffer, "add", 3) == 0)
        {
            // 处理添加员工信息请求
            char name[50];
            int age;
            char department[50];
            sscanf(buffer + 4, "%s %d %s", name, &age, department);

            char query[100];
            sprintf(query, "INSERT INTO employees (name, age, department) VALUES ('%s', %d, '%s');", name, age, department);

            if (mysql_query(conn, query))
            {
                fprintf(stderr, "%s\n", mysql_error(conn));
                write(client_sock, "error", 5);
                return;
            }

            write(client_sock, "success", 7);
        }
        else if (strncmp(buffer, "view", 4) == 0)
        {
            // 处理浏览员工信息请求
            handle_view(client_sock, conn);
        }
        else if (strncmp(buffer, "modify", 6) == 0)
        {
            // 处理修改员工信息请求
            handle_modify(client_sock, conn, buffer);
        }
        else if (strncmp(buffer, "search", 6) == 0)
        {
            // 处理查询员工信息请求
            handle_search(client_sock, conn, buffer);
        }
        else if (strncmp(buffer, "delete", 6) == 0)
        {
            // 处理删除员工信息请求
            handle_delete(client_sock, conn, buffer);
        }
        else
        {
            write(client_sock, "invalid command", 16);
        }
    }
}

void handle_view(int client_sock, MYSQL *conn)
{
    char query[100] = "SELECT * FROM employees;";
    if (mysql_query(conn, query))
    {
        fprintf(stderr, "%s\n", mysql_error(conn));
        write(client_sock, "error", 5);
        return;
    }

    MYSQL_RES *result = mysql_store_result(conn);
    if (!result)
    {
        fprintf(stderr, "%s\n", mysql_error(conn));
        write(client_sock, "error", 5);
        return;
    }

    int num_fields = mysql_num_fields(result);
    MYSQL_ROW row;

    while ((row = mysql_fetch_row(result)))
    {
        for (int i = 0; i < num_fields; i++)
            write(client_sock, row[i], strlen(row[i]));
        write(client_sock, "\n", 1);
    }

    mysql_free_result(result);
    write(client_sock, "success", 7);
}

void handle_modify(int client_sock, MYSQL *conn, char *buffer)
{
    char name[50];
    int age;
    char department[50];
    sscanf(buffer + 7, "%s %d %s", name, &age, department);

    char query[100];
    sprintf(query, "UPDATE employees SET age=%d, department='%s' WHERE name='%s'", age, department, name);

    if (mysql_query(conn, query))
    {
        fprintf(stderr, "%s\n", mysql_error(conn));
        write(client_sock, "error", 5);
        return;
    }

    if (mysql_affected_rows(conn) == 0)
    {
        write(client_sock, "no such employee", 17);
        return;
    }

    write(client_sock, "success", 7);
}

void handle_search(int client_sock, MYSQL *conn, char *buffer)
{
    char name[50];
    sscanf(buffer + 7, "%s", name);

    char query[100];
    sprintf(query, "SELECT * FROM employees WHERE name='%s'", name);

    if (mysql_query(conn, query))
    {
        fprintf(stderr, "%s\n", mysql_error(conn));
        write(client_sock, "error", 5);
        return;
    }

    MYSQL_RES *result = mysql_store_result(conn);
    if (!result)
    {
        fprintf(stderr, "%s\n", mysql_error(conn));
        write(client_sock, "error", 5);
        return;
    }

    int num_rows = mysql_num_rows(result);
    if (num_rows == 0)
    {
        write(client_sock, "no such employee", 17);
        return;
    }

    MYSQL_ROW row = mysql_fetch_row(result);

    for (int i = 0; i < mysql_num_fields(result); i++)
        write(client_sock, row[i], strlen(row[i]));
    write(client_sock, "\n", 1);

    mysql_free_result(result);
    write(client_sock, "success", 7);
}

void handle_delete(int client_sock, MYSQL *conn, char *buffer)
{
    char name[50];
    sscanf(buffer + 7, "%s", name);

    char query[100];
    sprintf(query, "DELETE FROM employees WHERE name='%s'", name);

    if (mysql_query(conn, query))
    {
        fprintf(stderr, "%s\n", mysql_error(conn));
        write(client_sock, "error", 5);
        return;
    }

    if (mysql_affected_rows(conn) == 0)
    {
        write(client_sock, "no such employee", 17);
        return;
    }

    write(client_sock, "success", 7);
}

注意：此示例仅供参考，不可直接用于生产环境。在实际应用中，需要对代码进行适当修改和优化，以确保安全性和可靠性。