rewrite number whatever to .net and blazor.

Pages/Unsubscribe.cshtml.cs

@@ -0,0 +1,45 @@
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.RazorPages;
+using Microsoft.EntityFrameworkCore;
+using landing.Data;
+
+namespace landing.Pages;
+
+public class UnsubscribeModel : PageModel
+{
+    private readonly AppDbContext _db;
+    private readonly ILogger<UnsubscribeModel> _logger;
+
+    public UnsubscribeModel(AppDbContext db, ILogger<UnsubscribeModel> logger)
+    {
+        _db = db;
+        _logger = logger;
+    }
+
+    public string ResultMessage { get; set; } = string.Empty;
+
+    public async Task<IActionResult> OnGetAsync([FromQuery] string? email)
+    {
+        if (string.IsNullOrWhiteSpace(email))
+        {
+            Response.StatusCode = 400;
+            ResultMessage = "No email specified";
+            return Page();
+        }
+
+        var subscriber = await _db.Subscribers.FirstOrDefaultAsync(s => s.Email == email);
+        if (subscriber == null)
+        {
+            Response.StatusCode = 400;
+            ResultMessage = $"Email {email} was not found or already unsubscribed";
+            return Page();
+        }
+
+        _db.Subscribers.Remove(subscriber);
+        await _db.SaveChangesAsync();
+
+        _logger.LogInformation("Unsubscribed {Email}", email);
+        ResultMessage = $"The email {email} has been unsubscribed.";
+        return Page();
+    }
+}