用mvc实现简单的增删改查

好的，下面是用MVC实现简单的增删改查的步骤：

1. 创建一个Model类，用于定义数据结构和操作数据库的方法。例如：

public class User {
    public int Id { get; set; }
    public string Name { get; set; }
    public string Email { get; set; }
    public string Password { get; set; }
}

public class UserModel {
    public List<User> GetAllUsers() {
        // 查询数据库中的所有用户
    }

    public User GetUserById(int id) {
        // 根据ID查询用户
    }

    public void AddUser(User user) {
        // 添加用户到数据库
    }

    public void UpdateUser(int id, User user) {
        // 更新指定ID的用户信息
    }

    public void DeleteUser(int id) {
        // 删除指定ID的用户
    }
}

2. 创建一个Controller类，用于处理用户的请求，调用Model类的方法来操作数据库，并返回视图。例如：

public class UserController : Controller {
    private UserModel userModel = new UserModel();

    public ActionResult Index() {
        List<User> userList = userModel.GetAllUsers();
        return View(userList);
    }

    public ActionResult Details(int id) {
        User user = userModel.GetUserById(id);
        return View(user);
    }

    public ActionResult Create() {
        return View();
    }

    [HttpPost]
    public ActionResult Create(User user) {
        if (ModelState.IsValid) {
            userModel.AddUser(user);
            return RedirectToAction("Index");
        }
        return View(user);
    }

    public ActionResult Edit(int id) {
        User user = userModel.GetUserById(id);
        return View(user);
    }

    [HttpPost]
    public ActionResult Edit(int id, User user) {
        if (ModelState.IsValid) {
            userModel.UpdateUser(id, user);
            return RedirectToAction("Index");
        }
        return View(user);
    }

    public ActionResult Delete(int id) {
        User user = userModel.GetUserById(id);
        return View(user);
    }

    [HttpPost]
    public ActionResult Delete(int id, FormCollection collection) {
        userModel.DeleteUser(id);
        return RedirectToAction("Index");
    }
}

3. 创建视图文件（.cshtml）来显示数据和处理用户输入。例如：

Index.cshtml:

@model List<User>

<table>
    <tr>
        <th>ID</th>
        <th>Name</th>
        <th>Email</th>
        <th>Password</th>
        <th>Actions</th>
    </tr>
@foreach (var user in Model) {
    <tr>
        <td>@user.Id</td>
        <td>@user.Name</td>
        <td>@user.Email</td>
        <td>@user.Password</td>
        <td>
            @Html.ActionLink("Details", "Details", new { id = user.Id }) |
            @Html.ActionLink("Edit", "Edit", new { id = user.Id }) |
            @Html.ActionLink("Delete", "Delete", new { id = user.Id })
        </td>
    </tr>
}
</table>

@Html.ActionLink("Create New User", "Create")

Details.cshtml:

@model User

<h2>@Model.Name</h2>

<p>Email: @Model.Email</p>
<p>Password: @Model.Password</p>

@Html.ActionLink("Edit", "Edit", new { id = Model.Id }) |
@Html.ActionLink("Delete", "Delete", new { id = Model.Id })

Create.cshtml:

@model User

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)

    <div>
        @Html.LabelFor(model => model.Name)
        @Html.EditorFor(model => model.Name)
        @Html.ValidationMessageFor(model => model.Name)
    </div>

    <div>
        @Html.LabelFor(model => model.Email)
        @Html.EditorFor(model => model.Email)
        @Html.ValidationMessageFor(model => model.Email)
    </div>

    <div>
        @Html.LabelFor(model => model.Password)
        @Html.EditorFor(model => model.Password)
        @Html.ValidationMessageFor(model => model.Password)
    </div>

    <p>
        <input type="submit" value="Create" />
    </p>
}

@Html.ActionLink("Back to List", "Index")

Edit.cshtml:

@model User

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
    @Html.HiddenFor(model => model.Id)

    <div>
        @Html.LabelFor(model => model.Name)
        @Html.EditorFor(model => model.Name)
        @Html.ValidationMessageFor(model => model.Name)
    </div>

    <div>
        @Html.LabelFor(model => model.Email)
        @Html.EditorFor(model => model.Email)
        @Html.ValidationMessageFor(model => model.Email)
    </div>

    <div>
        @Html.LabelFor(model => model.Password)
        @Html.EditorFor(model => model.Password)
        @Html.ValidationMessageFor(model => model.Password)
    </div>

    <p>
        <input type="submit" value="Save" />
    </p>
}

@Html.ActionLink("Back to List", "Index")

Delete.cshtml:

@model User

<h2>Are you sure you want to delete this user?</h2>

<p>@Model.Name</p>

@using (Html.BeginForm()) {
    <input type="submit" value="Delete" />
}

@Html.ActionLink("Cancel", "Index")

这样，我们就用MVC实现了一个简单的增删改查功能。