ASP.NET Core MVC 接上篇新增加“增删改查”操作

前言

由于上一篇文章只写了怎么创建项目以及一个查询操作，这篇文章将把增删改查的操作补齐，希望能帮助到一同学习的小伙伴，内容中如有不懂的点，可参考ASP.NET Core官方文档，如有写的不对的，请在评论区补充，主打听劝；

增删改查

接口类

    public interface IGetService<T> where T : class
    {
        /// <summary>
        /// 查询
        /// </summary>
        /// <returns></returns>
        List<T> GetIDservice(string name);

        /// <summary>
        /// 新增
        /// </summary>
        /// <param name="a">插入的对象</param>
        /// <returns></returns>
        int AddService(T a);

       /// <summary>
       /// 修改
       /// </summary>
       /// <param name="u">对象</param>
       /// <returns></returns>
        int UpServeice(T u);

       /// <summary>
       /// 删除
       /// </summary>
       /// <param name="id">对象ID</param>
       /// <returns></returns>
        int DelServive(int id);

        /// <summary>
        /// 根据ID查询对象
        /// </summary>
        /// <param name="id"></param>
        /// <returns></returns>
        T GetValue(int id);
    }

实现类

    public class GetsService : IGetService<Student>
    {
        private readonly WebDbContext _db;
        public GetsService(WebDbContext db)
        {
            _db = db;
        }

        //新增方法
        public int AddService(Student a)
        {
            _db.Students.Add(a);
            return _db.SaveChanges();

        }

        //删除方法
        public int DelServive(int id)
        {
            _db.Students.Remove(new Student { Id=id});
            return _db.SaveChanges();
        }

        //查询所有或根据id进行查询
        public List<Student> GetIDservice(string name)
        {
            var list=_db.Students.ToList();
            if (!string.IsNullOrEmpty(name))
            {
                list=list.Where(x => x.Name!.Contains(name)).ToList();
            }
            return list;
        }
        //根据id查询信息
        public Student GetValue(int id)
        {
           return _db.Students.First(x => x.Id==id); 
        }

        //修改方法
        public int UpServeice(Student u)
        {
           var list =_db.Students.Where(e=>e.Id==u.Id).First();
            list.Name= u.Name;
            list.Age=u.Age;
            list.Sex=u.Sex;
            list.Address=u.Address;
            return _db.SaveChanges();
        }
        
    }

控制器

    public class StudentController : Controller
    {
        private readonly IGetService<Student> _service;
        public StudentController(IGetService<Student> service)
        {
            _service = service;
        }

        //查询所有以及根据姓名查询
        public IActionResult Index(string name)
        {
            var list = _service.GetIDservice(name);
            return View(list);
        }

        //添加数据
        [HttpGet]
        public IActionResult Add()
        {
            return View();
        }
        [HttpPost]
        public IActionResult Add(Student student)
        {
            if (ModelState.IsValid)
            {
                Student student1 = new Student();
                student1.Name = student.Name;
                student1.Age = student.Age;
                student1.Sex = student.Sex;
                student1.Address = student.Address;
                _service.AddService(student1);
                return RedirectToAction(nameof(Index));
            }
            return View();
        }

        //根据ID修改数据
        [HttpGet]
        public IActionResult Edit(int id)
        {
            var stu = _service.GetValue(id);
            return View(stu);
        }
        [HttpPost]
        public IActionResult Edit(Student student)
        {
            if (ModelState.IsValid)
            {
                _service.UpServeice(student);
                return RedirectToAction(nameof(Index));
            }
            return View();
        }

        //根据id删除数据
        public IActionResult Del(int id)
        {

            _service.DelServive(id);
            return RedirectToAction(nameof(Index));
        }
    }

视图

查询视图

@{
    ViewData["Title"] = "查询所有";
}
@model List<Student>
<div>
    <p><a asp-action="Add">添加学生信息</a></p>
    <form asp-controller="Student" asp-action="Index" method="get">
        <label>输入姓名：</label><input name="name" /><input  type="submit"/>
    </form>
    <table class="table table-bordered">
        <tr>
            <td>姓名</td>
            <td>年龄</td>
            <td>性别</td>
            <td>住址</td>
            <td>操作</td>
        </tr>
        @foreach (var item in Model)
        {
            <tr>
                <td>@item.Name</td>
                <td>@item.Age</td>
                @if (item.Sex == true)
                {
                    <td>男</td>
                }
                else
                {
                    <td>女</td>
                }
                <td>@item.Address</td>
                <td>
                    <a asp-route-id="@item.Id" asp-action="Edit">编辑</a> | 
                    <a asp-route-id="@item.Id" asp-action="Del" onclick="return confirm('确定删除吗？')">删除</a>
                </td>
            </tr>
        }
    </table>
</div>

修改视图

@{
}
@model Student
<h2>修改数据</h2>
<form asp-controller="Student" asp-action="Edit" method="post">
    <p><label>姓名</label> <input asp-for="Name" /></p>
    <p><label>年龄</label> <input asp-for="Age" /></p>
    <p><label>性别</label> <input asp-for="Sex" type="checkbox" /></p>
    <p><label>住址</label> <input asp-for="Address" /></p>
    <p><input type="submit" value="确定修改" /></p>
</form>

新增视图

@{
}
@model Student
<h2>添加数据</h2>
<form asp-controller="Student" asp-action="Add" method="post">
    <p><label>姓名</label> <input asp-for="Name" /></p>
    <p><label>年龄</label> <input asp-for="Age" /></p>
    <p><label>性别</label> <input asp-for="Sex" type="checkbox"/></p>
    <p><label>住址</label> <input asp-for="Address" /></p>
    <p><input type="submit" value="确定添加" /></p>
</form>

效果图