C# Help with a table that sends an email to a person when submitted

[Gaurav]

I am a very beginner coder who is trying to make a table on C# in which I'm making a requisition slip which a person can enter data on and submit. When the data is submitted the data gets sent to a desired email but i keep getting errors like
"An unhandled exception occurred while processing the request."
How do I fix my code?


using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using System;
using System.Collections.Generic;
using System.Net;
using System.Net.Mail;
using Microsoft.Extensions.Logging;

namespace BestStore.Pages
{
public class PrivacyModel : PageModel
{
private readonly ILogger<PrivacyModel> _logger;

// This will hold the requisition data from the form
[BindProperty]
public List<RequisitionItem> RequisitionItems { get; set; } = new List<RequisitionItem>();

// Added property for the person's name requesting the items
[BindProperty]
public string? Name { get; set; } // Name of the person requesting, nullable

public PrivacyModel(ILogger<PrivacyModel> logger)
{
_logger = logger;

// Initialize the list of items with 21 empty rows (for 21 products)
for (int i = 0; i < 21; i++)
{
RequisitionItems.Add(new RequisitionItem());
}
}

// OnGet method is executed when the page is first loaded
public void OnGet()
{
}

// This method is triggered when the form is submitted
public IActionResult OnPostSubmit()
{
// Prepare the requisition details to send in the email
var requisitionDetails = "Requisition Slip\n\n";
requisitionDetails += "Name: " + (Name ?? "Not provided") + "\n";
requisitionDetails += "Date: " + DateTime.Now.ToString("yyyy-MM-dd") + "\n\n";

// Loop through the list of requisition items and add their details
foreach (var item in RequisitionItems)
{
requisitionDetails += $"Product: {(item.ProductName ?? "Not provided")}\n";
requisitionDetails += $"Weight: {(item.Weight ?? "Not provided")}\n";
requisitionDetails += $"Type: {(item.Type ?? "Not provided")}\n";
requisitionDetails += $"Quantity Requested: {(item.QuantityRequested?.ToString() ?? "Not provided")}\n";
requisitionDetails += $"Quantity Issued: {(item.QuantityIssued?.ToString() ?? "Not provided")}\n";
requisitionDetails += $"Remarks: {(item.Remarks ?? "Not provided")}\n";
requisitionDetails += "\n";
}

// Send the requisition details to the email address
SendEmail("[email protected]", "Requisition Slip", requisitionDetails);

// Redirect to a Thank You page or a success message
return RedirectToPage("Index"); // Make sure you have a ThankYou page or handle the response
}

// Method to send the requisition data via email using Gmail SMTP
private void SendEmail(string toEmail, string subject, string body)
{
try
{
var fromEmail = "[email protected]"; // Replace with your Gmail address
var appPassword = "your-app-password"; // Replace with the App Password generated for Gmail

var smtpClient = new SmtpClient("smtp.gmail.com")
{
Port = 587,
Credentials = new NetworkCredential(fromEmail, appPassword), // Gmail credentials
EnableSsl = true,
};

var mailMessage = new MailMessage
{
From = new MailAddress(fromEmail),
Subject = subject,
Body = body,
IsBodyHtml = false, // Set to true if you're sending HTML emails
};
mailMessage.To.Add(toEmail);

// Send the email
smtpClient.Send(mailMessage);
}
catch (Exception ex)
{
// Log the error or handle the failure case (e.g., show a message to the user)
_logger.LogError("Error sending email: " + ex.Message);
}
}
}

// Class to represent a single requisition item (row in the table)
public class RequisitionItem
{
// Nullable strings - No changes needed for these properties
public string? ProductName { get; set; } // Nullable string
public string? Weight { get; set; } // Nullable string
public string? Type { get; set; } // Nullable string
public string? Remarks { get; set; } // Nullable string

// Nullable integers for quantities
public int? QuantityRequested { get; set; } // Nullable integer
public int? QuantityIssued { get; set; } // Nullable integer
}
}

 

[JimmysNetwork]

Sorry for the late response.

Possible Issues & Fixes​

1. SMTP Configuration Issue (Email Sending Error)
   
   • You need to ensure that your Gmail account allows "Less Secure Apps" or use an App Password (which you’ve mentioned, but ensure it's valid).
   • If there’s an issue with SMTP (like incorrect credentials, port, or SSL), it can cause an exception.
   • Solution: Try using smtpClient.SendAsync(mailMessage, null) instead of smtpClient.Send(mailMessage) for better debugging.
     
2. Logging More Details About Exceptions
   
   • Instead of just logging ex.Message, log the entire stack trace:
     

     _logger.LogError($"Error sending email: {ex}");

3. Ensure The Form Data is Passed Correctly
   
   • Check if RequisitionItems is properly populated when OnPostSubmit() is called.
   • If it’s null, it means the form isn’t binding correctly.
4. Improve Debugging: Add Try-Catch for OnPostSubmit

public IActionResult OnPostSubmit()
{
    try
    {
        // Prepare the email
        var requisitionDetails = $"Requisition Slip\n\nName: {(Name ?? "Not provided")}\nDate: {DateTime.Now:yyyy-MM-dd}\n\n";
        
        foreach (var item in RequisitionItems)
        {
            requisitionDetails += $"Product: {(item.ProductName ?? "Not provided")}\n";
            requisitionDetails += $"Quantity: {(item.QuantityRequested?.ToString() ?? "Not provided")}\n\n";
        }

        SendEmail("[email protected]", "Requisition Slip", requisitionDetails);
        return RedirectToPage("Index");
    }
    catch (Exception ex)
    {
        _logger.LogError($"An error occurred: {ex}");
        ModelState.AddModelError("", "Something went wrong. Please try again.");
        return Page();
    }
}

Let me know if this helps. If not we can go back to the drawing board.