read certificate store post

Author: Rick Neeft

_posts/2025-11-26-certificates-current-user.md

@@ -0,0 +1,90 @@
+---
+title: View all certificates in User store
+date: 2025-11-26 17:04:00 +0100
+categories: [dotnet, certificates]
+tags: [dotnet, certificates, thumbprints]     # TAG names should always be lowercase
+---
+
+This short post shows how to list certificates from the Current User (Personal) certificate store using C#. The code below prints a table with certificate thumbprints and the certificate common name (CN). It uses `Spectre.Console` to render a friendly table but the certificate logic itself does not depend on that library.
+
+Usage notes:
+
+- The snippet reads from the Current User personal store (`StoreName.My`, `StoreLocation.CurrentUser`).
+- Thumbprints are printed in-dim to make them easy to copy; CN is truncated to 40 characters for readability.
+
+```charp
+#: package Spectre.Console@0.49.1
+
+using System;
+using System.Security.Cryptography.X509Certificates;
+using Spectre.Console;
+using System.Text.RegularExpressions;
+using System.Linq;
+
+// Query the Current User - Personal certificate store
+var store = new X509Store(StoreName.My, StoreLocation.CurrentUser);
+
+try
+{
+    // Open the certificate store in read-only mode
+    store.Open(OpenFlags.ReadOnly);
+    
+    // Get all certificates from the store
+    var certificates = store.Certificates;
+    
+    if (certificates.Count == 0)
+    {
+        AnsiConsole.MarkupLine("[yellow]No certificates found in the Current User - Personal store.[/]");
+        return;
+    }
+    
+    // Create a table to display the certificates
+    var table = new Table();
+    table.AddColumn("[bold]Thumbprint[/]");
+    table.AddColumn("[bold]Common Name (CN)[/]");
+    
+    // Sort certificates alphabetically by thumbprint and add to table
+    foreach (X509Certificate2 cert in certificates.Cast<X509Certificate2>().OrderBy(c => c.Thumbprint))
+    {
+        // Extract CN from subject using regex
+        var subject = cert.Subject ?? "";
+        var cnMatch = Regex.Match(subject, @"CN=([^,]+)");
+        var commonName = cnMatch.Success ? cnMatch.Groups[1].Value.Trim() : "N/A";
+        
+        // Trim CN to 40 characters
+        if (commonName.Length > 40)
+        {
+            commonName = commonName.Substring(0, 40) + "...";
+        }
+        
+        var thumbprint = cert.Thumbprint ?? "N/A";
+        
+        table.AddRow(
+            $"[dim]{thumbprint}[/]",
+            commonName.EscapeMarkup()
+        );
+    }
+    
+    // Display header
+    AnsiConsole.MarkupLine($"[green]Found {certificates.Count} certificate(s) in Current User - Personal store:[/]");
+    AnsiConsole.WriteLine();
+    
+    // Render the table
+    AnsiConsole.Write(table);
+}
+catch (Exception ex)
+{
+    AnsiConsole.MarkupLine($"[red]Error accessing certificate store: {ex.Message}[/]");
+}
+finally
+{
+    // Always close the store
+    store.Close();
+}
+```
+
+Run with the new single-file `dotnet run` feature (example assumes the file is named `list-certs.cs`):
+
+```pwsh
+dotnet run .\list-certs.cs
+```