MVC实现删除数据库记录：从原理到实践

// 数据实体类（Model）
public class Product
{
    public int Id { get; set; }
    public string Name { get; set; }
    public decimal Price { get; set; }
    public bool IsDeleted { get; set; } // 软删除标记
}
 
// 数据访问层（Model的一部分）
public class AppDbContext : DbContext
{
    public DbSet<Product> Products { get; set; }
 
    public AppDbContext(DbContextOptions<AppDbContext> options) : base(options) { }
}
 
// 业务逻辑服务（Model层封装）
public class ProductService
{
    private readonly AppDbContext _context;
 
    public ProductService(AppDbContext context)
    {
        _context = context;
    }
 
    // 硬删除：直接从数据库删除记录
    public async Task HardDeleteAsync(int id)
    {
        var product = await _context.Products.FindAsync(id);
        if (product == null)
            throw new KeyNotFoundException("记录不存在");
        
        _context.Products.Remove(product);
        await _context.SaveChangesAsync();
    }
 
    // 软删除：标记IsDeleted=true，不实际删除记录
    public async Task SoftDeleteAsync(int id)
    {
        var product = await _context.Products.FindAsync(id);
        if (product == null)
            throw new KeyNotFoundException("记录不存在");
        
        product.IsDeleted = true;
        await _context.SaveChangesAsync();
    }
}

<!-- Views/Product/Index.cshtml -->
@model IEnumerable<Product>
 
<table class="table">
    <thead>
        <tr>
            <th>ID</th>
            <th>名称</th>
            <th>价格</th>
            <th>操作</th>
        </tr>
    </thead>
    <tbody>
        @foreach (var item in Model)
        {
            <tr>
                <td>@item.Id</td>
                <td>@item.Name</td>
                <td>@item.Price</td>
                <td>
                    <!-- 方式1：表单提交（推荐，支持DELETE方法） -->
                    <form asp-action="Delete" asp-route-id="@item.Id" method="post" 
                          onsubmit="return confirm('确定删除 @item.Name 吗？');">
                        <button type="submit" class="btn btn-danger">删除</button>
                    </form>
 
                    <!-- 方式2：AJAX异步删除 -->
                    <button class="btn btn-danger" onclick="deleteProduct(@item.Id, '@item.Name')">
                        AJAX删除
                    </button>
                </td>
            </tr>
        }
    </tbody>
</table>
 
@section Scripts {
    <script>
        function deleteProduct(id, name) {
            if (!confirm(`确定删除 ${name} 吗？`)) return;
 
            fetch(`/Product/Delete/${id}`, {
                method: 'DELETE',
                headers: { 'Content-Type': 'application/json' },
                // 需添加防CSRF令牌（ASP.NET Core自动处理）
                headers: { 'RequestVerificationToken': document.querySelector('input[name="__RequestVerificationToken"]').value }
            })
            .then(response => {
                if (response.ok) {
                    location.reload(); // 刷新页面
                } else {
                    alert('删除失败，请重试');
                }
            });
        }
    </script>
}

[Authorize(Roles = "Admin")] // 权限校验：仅管理员可删除
public class ProductController : Controller
{
    private readonly ProductService _productService;
 
    public ProductController(ProductService productService)
    {
        _productService = productService;
    }
 
    // GET: 展示产品列表（View层入口）
    public async Task<IActionResult> Index()
    {
        var products = await _productService.GetAllAsync(); // 获取未删除的记录（软删除场景）
        return View(products);
    }
 
    // POST: 处理表单提交的删除请求（传统方式）
    [HttpPost]
    [ValidateAntiForgeryToken] // 防CSRF攻击
    public async Task<IActionResult> Delete(int id)
    {
        try
        {
            await _productService.SoftDeleteAsync(id); // 调用软删除
            TempData["SuccessMessage"] = "删除成功";
        }
        catch (KeyNotFoundException ex)
        {
            TempData["ErrorMessage"] = ex.Message;
        }
        return RedirectToAction(nameof(Index)); // 重定向到列表页
    }
 
    // DELETE: 处理AJAX删除请求（RESTful风格）
    [HttpDelete]
    public async Task<IActionResult> Delete(int id)
    {
        try
        {
            await _productService.SoftDeleteAsync(id);
            return Ok(new { success = true });
        }
        catch (Exception ex)
        {
            return BadRequest(new { success = false, message = ex.Message });
        }
    }
}

private readonly ILogger<ProductController> _logger;
 
[HttpDelete]
public async Task<IActionResult> Delete(int id)
{
    var userName = User.Identity.Name;
    _logger.LogInformation($"用户 {userName} 尝试删除产品 ID: {id}");
    try
    {
        await _productService.SoftDeleteAsync(id);
        _logger.LogInformation($"用户 {userName} 成功删除产品 ID: {id}");
        return Ok();
    }
    catch (Exception ex)
    {
        _logger.LogError(ex, $"用户 {userName} 删除产品 ID: {id} 失败");
        return BadRequest("删除失败：" + ex.Message);
    }
}