I have a ProductsController with an Index method. This Index method contains a.Where() part that looks through the database with the users input. (for example: "Apples, Banana's, Exotic, etc.") When there are no results found it throws an error: "Sequence contains no elements" which is logical.
When the errors throws, I want it to be displayed in an AlertBox. I have followed this thread but I can't seem to get the error to the View.
My Index Method:
public ActionResult Index(string item = "APPE", int amount = 0)
{
var CurrentCulture = System.Threading.Thread.CurrentThread.CurrentCulture.Name;
ViewData["Amount"] = amount;
//Uses the Logged in Username to match the items related to it's CompanyNr
var LoggedUser = Convert.ToInt32(User.Identity.Name);
Dr dr = _context.Dr.Where(x => x.CompanyNr == LoggedUser).First();
var itemCheck = item != null ? item.ToUpper() : "";
try
{
// It throws the Error right here. because there are no elements matching in _context.Th
var currentCat = _context.Th.Where(x => x.CategoryCode.Contains(itemCheck)).First();
Console.WriteLine("My currentCat is: " + currentCat.ToString());
if (itemCheck == "")
{
ViewData["Category"] = "All Products";
}
else
{
//Displays the Categories on the Users chosen language
ViewData["Category"] = CurrentCulture switch
{
"en-US" => currentCat.NameEnglish,
"nl-NL" => currentCat.NameDutch,
"de-DE" => currentCat.NameGerman,
"da-DK" => currentCat.NameFrench,
_ => currentCat.NameEnglish,
};
var SearchItem = _context.Products
.Where(x => x.CompanyNr == LoggedUser)
.Where(x => x.CategoryCode.Contains(itemCheck));
#section A copy of the products for the users shopping cart called newProducts
#endregion
return View(newProducts);
}
catch (Exception ex)
{
//ex.Message contains "Sequence contains no elements"
ModelState.AddModelError("Error", ex.Message);
//return View("Index");
return View("Index");
}
}
My View
<div id="FilterList">
<ul>
<li>
<form method="get" asp-action="Index" asp-controller="Products">
<input type="hidden" name="item" value="" />
<button type="submit">@Localizer["Show All"]</button>
</form>
</li>
</ul>
<ul>
@foreach (var item in ViewData["Main_Items"] as IEnumerable<Project.Models.DataBase.Th>)
{
<li>
<form method="get" asp-action="Index" asp-controller="Products">
@switch (CurrentCulture)
{
case "nl-NL":
<input type="hidden" name="item" value="@item.CategoryCode.Trim()" />
<button type="submit">@item.NameDutch</button> break;
case "en-US":
<input type="hidden" name="item" value="@item.CategoryCode.Trim()" />
<button type="submit">@item.NameEnglish</button> break;
case "de-DE":
<input type="hidden" name="item" value="@item.CategoryCode.Trim()" />
<button type="submit">@item.NameGerman</button> break;
case "da-DK":
<input type="hidden" name="item" value="@item.CategoryCode.Trim()" />
<button type="submit">@item.NameFrench</button> break;
default:
<input type="hidden" name="item" value="@item.CategoryCode.Trim()" />
<button type="submit">@item.NameEnglish</button>
break;
}
</form>
</li>
}
</ul>
</div>
The JavaScript that is supposed to show the AlertBox
/*If the model is not valid and there is more than 0 "Error", Show an Alert with it's error*/
@if (!ViewData.ModelState.IsValid && ViewData.ModelState["Error"].Errors.Count > 0)
{
<text>
$(document).ready(function () {
alert('@ViewData.ModelState["Error"].Errors.First().ErrorMessage');
/*It's not logging anything..*/
console.log('@ViewData.ModelState["Error"].Errors.First().ErrorMessage');
});
</text>
}
I feel like i'm missing something important which I am not finding. I hope I have given enough explanation in both the code and my summary to help find the solution.
After my test, I found that there is no problem with your code, and it works very well for me. You can check your code based on my simple example below.
View:
<form asp-action="Create">
<div class="form-group">
<label asp-for="Id" class="control-label"></label>
<input asp-for="Id" class="form-control" />
</div>
<div class="form-group">
<label asp-for="Name" class="control-label"></label>
<input asp-for="Name" class="form-control" />
</div>
<div class="form-group">
<input type="submit" value="Create" class="btn btn-primary" />
</div>
</form>
@section Scripts {
<script type="text/javascript">
@if (!ViewData.ModelState.IsValid && ViewData.ModelState["Error"].Errors.Count > 0)
{
<text>
$(document).ready(function () {
alert('@ViewData.ModelState["Error"].Errors.First().ErrorMessage');
/*It's not logging anything..*/
console.log('@ViewData.ModelState["Error"].Errors.First().ErrorMessage');
});
</text>
}
</script>
}
Action:
public IActionResult Create()
{
return View();
}
[HttpPost]
public IActionResult Create(Student student)
{
try
{
var m = _context.Student.Where(c => c.Name.Contains("bb")).First();
return View();
}
catch (Exception ex)
{
ModelState.AddModelError("Error", ex.Message);
return View("Create");
}
}
You can check as follow steps:
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