added asp-controller to editserver.cshtml + using id in edtiserver as hidden

Watcher/Controllers/ServerController.cs

@@ -96,24 +96,34 @@ public class ServerController : Controller
     [ValidateAntiForgeryToken]
     public async Task<IActionResult> EditServer(int id, EditServerViewModel vm)
     {
-        if (ModelState.IsValid)
+        if (!ModelState.IsValid)
         {
+            return View(vm);
+        }
+
         var server = await _context.Servers.FindAsync(id);
-            if (server == null) return NotFound();
+        if (server == null)
+        {
+            return NotFound();
+        }
 
         server.Name = vm.Name;
         server.IPAddress = vm.IPAddress;
         server.Type = vm.Type;
 
+        try
+        {
             await _context.SaveChangesAsync();
-
             _logger.LogInformation("Server '{server}' erfolgreich aktualisiert", server.Name);
-
             return RedirectToAction(nameof(Overview));
         }
-
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Fehler beim Speichern des Servers");
+            ModelState.AddModelError("", "Fehler beim Speichern");
             return View(vm);
         }
+    }
 
     // GET: Server/Details/5
     [HttpGet]

Watcher/ViewModels/EditServerViewModel.cs

@@ -1,10 +1,19 @@
-namespace Watcher.ViewModels;
+using System.ComponentModel.DataAnnotations;
 
+namespace Watcher.ViewModels
+{
     public class EditServerViewModel
     {
-    public string Name { get; set; } = string.Empty;
+        public int Id { get; set; }
 
-    public string IPAddress { get; set; } = string.Empty;
+        [Required(ErrorMessage = "Name ist erforderlich")]
+        public string Name { get; set; }
 
-    public string Type { get; set; } = "VPS";
+        [Required(ErrorMessage = "IP-Adresse ist erforderlich")]
+        [RegularExpression(@"^(?:[0-9]{1,3}\.){3}[0-9]{1,3}$", ErrorMessage = "Ungültige IP-Adresse")]
+        public string IPAddress { get; set; }
+
+        [Required(ErrorMessage = "Typ ist erforderlich")]
+        public string Type { get; set; }
+    }
 }

Watcher/Views/Server/EditServer.cshtml

@@ -1,4 +1,4 @@
-@model Watcher.ViewModels.EditServerViewModel;
+@model Watcher.ViewModels.EditServerViewModel
 
 @{
     ViewData["Title"] = "Server bearbeiten";
@@ -6,24 +6,26 @@
 
 <h2>Server bearbeiten</h2>
 
-<form asp-action="EditServer" method="post">
+<form asp-action="EditServer" asp-controller="Server" method="post">
     @Html.AntiForgeryToken()
+    <input type="hidden" asp-for="Id" />
 
     <div class="mb-3">
         <label asp-for="Name"></label>
         <input asp-for="Name" class="form-control" />
+        <span asp-validation-for="Name" class="text-danger"></span>
     </div>
 
     <div class="mb-3">
         <label asp-for="IPAddress"></label>
         <input asp-for="IPAddress" class="form-control" />
-    </div>
+        <span asp-validation-for="IPAddress" class="text-danger"></span>
-    
     </div>
 
     <div class="mb-3">
         <label asp-for="Type"></label>
         <input asp-for="Type" class="form-control" />
+        <span asp-validation-for="Type" class="text-danger"></span>
     </div>
 
     <button type="submit" class="btn btn-primary mt-3">Speichern</button>