我收到标题中提到的错误。
重要
表单成功将数据提交到数据库中，但随后尝试使用另一个查询再次提交，该查询尝试同时插入产品讨论 ID，然后失败/崩溃。我的项目中没有这样的查询。是什么原因造成的？
当 IDENTITY_INSERT 设置为 OFF 时，无法在表“讨论的产品”中插入标识列的显式值。
我查看了多个论坛帖子，并搜索了互联网，但仍然无法解决该问题。
联系报告将提交至数据库，产品讨论表也将更新。联系报告工作正常，但产品讨论表出现错误。
请参阅下面的所有代码：
ContactReportController[HttpGet]
public async Task<IActionResult> Submit()
{
var contactReport = new ContactReport
{
ProductsDiscussed = new List<ProductDiscussed>
{
new ProductDiscussed() // Add one default item
},
Report_Date = DateTime.Now
};
// Load necessary data for the form
await LoadFormDataAsync();
return View(contactReport);
}
[HttpPost]
public async Task<IActionResult> Submit(ContactReport contactReport)
{
if (User?.Identity?.IsAuthenticated == true)
{
if (ModelState.IsValid)
{
try
{
_logger.LogInformation("Model is valid. Adding contact report to context.");
// Add the ContactReport to the context
_context.ContactReports.Add(contactReport);
await _context.SaveChangesAsync();
// Ensure EF Core recognizes each product as a new entity
foreach (var product in contactReport.ProductsDiscussed)
{
// Set the foreign key
product.ReportID = contactReport.Report_Id;
// Mark the product as a new entity
_context.ProductsDiscussed.Add(product);
}
await _context.SaveChangesAsync();
return RedirectToAction("Index");
}
catch (Exception ex)
{
_logger.LogError(ex, "An error occurred while saving the contact report.");
ModelState.AddModelError("", "An error occurred while saving the report. Please try again.");
}
}
else
{
_logger.LogWarning("Model state is invalid.");
foreach (var error in ModelState.Values.SelectMany(v => v.Errors))
{
_logger.LogWarning(error.ErrorMessage);
}
}
}
else
{
_logger.LogWarning("User is not authenticated.");
return Unauthorized();
}
// Reload data if ModelState is invalid
await LoadFormDataAsync(); // Method to load the data needed for the form
return View(contactReport);
}
private async Task LoadFormDataAsync()
{
var staffList = await _context.Staff.OrderBy(s => s.Name).ToListAsync();
ViewBag.StaffList = new SelectList(staffList, "StaffId", "Name");
var countries = await _context.Countries.OrderBy(c => c.CountryName).ToListAsync();
ViewBag.Countries = new SelectList(countries, "CountryCode", "CountryName");
var productCategories = await _context.ProductCategories.OrderBy(c => c.CategoryName).ToListAsync();
ViewBag.ProductCategories = new SelectList(productCategories, "CategoryID", "CategoryName");
var customers = await _context.Customers.ToListAsync();
var customerList = customers
.Select(c => new
{
c.CustomerId,
DisplayName = string.IsNullOrEmpty(c.City)
? $"{c.Name} {c.Surname} - {c.Country}"
: $"{c.Name} {c.Surname} - {c.Country}, {c.City}",
SortKey = string.IsNullOrEmpty(c.Name) ? c.Surname : $"{c.Name} {c.Surname}"
})
.OrderBy(c => c.SortKey)
.ToList();
ViewBag.CustomerList = new SelectList(customerList, "CustomerId", "DisplayName");
}
Submit.cshtml<div id="productsContainer">
@for (int i = 0; i < Model.ProductsDiscussed.Count; i++)
{
<div class="card mb-3">
<div class="card-body">
<div class="form-group">
<label asp-for="ProductsDiscussed[i].BrandProductCategoriesID">Product Category</label>
<select asp-for="ProductsDiscussed[i].BrandProductCategoriesID" class="form-control" asp-items="ViewBag.ProductCategories">
<option value="">Select a product category</option>
</select>
<span asp-validation-for="ProductsDiscussed[i].BrandProductCategoriesID" class="text-danger"></span>
</div>
<div class="form-group">
<label asp-for="ProductsDiscussed[i].Sample">Sample Used</label>
<select asp-for="ProductsDiscussed[i].Sample" class="form-control">
<option value="false">No</option>
<option value="true">Yes</option>
</select>
<span asp-validation-for="ProductsDiscussed[i].Sample" class="text-danger"></span>
</div>
</div>
</div>
}
</div>
<button type="button" id="addProductButton" class="btn btn-secondary mt-3">Add Another Product</button>
SQL代码：
[Products Discussed ID] [int] IDENTITY(1,1) NOT NULL,
ContactReport.cspublic ContactReport()
{
ProductsDiscussed = new List<ProductDiscussed>();
}
// Text in-between
[NotMapped]
public List<ProductDiscussed> ProductsDiscussed { get; set; } = new List<ProductDiscussed>();
ProductDiscussed.cs[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
[Column("Products Discussed ID")]
public int ProductsDiscussedID { get; set; } // Manually managed ID
提交报告后出错：
CustomerDatabase.Controllers.ContactReportController：信息：模型有效。将联系人报告添加到上下文中。
Microsoft.EntityFrameworkCore.Database.Command：信息：执行的DbCommand [参数=[@p0='SUR238'（Nullable = false）（大小= 4000），@p1='test'（Nullable = false）（大小= 4000） 、 @p2='test' (Nullable = false) (大小 = 4000)、@p3='' (Nullable = false) (大小 = 4000)、@p4='test' (Nullable = false) (大小 = 4000) ，@p5='2024-08-12T00:00:00.0000000'，@p6='test'（可为空= false）（大小= 4000），@p7='STA11'（可为空= false）（大小= 4000）] , CommandType='文本', CommandTimeout='30']
将 IMPLICIT_TRANSACTIONS 设置为关闭；
不设置计数；
插入[联系人报告]（[客户 ID]、[反馈]、[跟进]、[位置]、[备注]、[报告日期]、[报告说明]、[员工 ID]）
输出已插入。[Id]
值（@p0、@p1、@p2、@p3、@p4、@p5、@p6、@p7）；抛出异常：Microsoft.Data.SqlClient.dll 中的“Microsoft.Data.SqlClient.SqlException”
Microsoft.EntityFrameworkCore.Database.Command：错误：执行 DbCommand 失败 [参数=[@p0='18'、@p1='3'、@p2='195'、@p3='False']、CommandType='Text ', CommandTimeout='30']Microsoft.EntityFrameworkCore.DbUpdateException：保存实体更改时发生错误。有关详细信息，请参阅内部异常。
Microsoft.Data.SqlClient.SqlException（0x80131904）：当 IDENTITY_INSERT 设置为 OFF 时，无法在表“讨论的产品”中插入标识列的显式值。
数据库对您未执行的插入进行神秘投诉的两个常见原因：