Troubleshooting Issue with Displaying Disposable Email Column in C# Email Validation Tool

Are you facing difficulties in displaying the disposable email column in your C# email validation tool’s DataGridView? If yes, then you’ve come to the right place! In this article, we will explore a code snippet and discuss potential issues that might be causing the problem.

The Problem

In your C# email validation tool, you have successfully implemented the display of valid and bad email addresses in the DataGridView. However, you are encountering an issue with the disposable email column. Despite ensuring that the disposableEmails list contains the correct addresses, the respective cells in the DataGridView remain empty.

Code Snippet

Let’s take a look at the relevant code snippet that populates the DataGridView:

private async void guna2Button4_Click_1(object sender, EventArgs e)
{
    try
    {
        // Clear lists before validation
        validEmails.Clear();
        badEmails.Clear();
        disposableEmails.Clear();

        // Read emails from the selected file
        string[] emails = File.ReadAllLines(selectedFilePath);

        // Perform email validation and categorize them accordingly
        foreach (string email in emails)
        {
            if (IsValidEmail(email))
            {
                validEmails.Add(email);
            }
            else if (IsValidEmailSyntax(email))
            {
                badEmails.Add(email);
            }
            else
            {
                // Check if email is disposable
                bool isDisposable = await IsDisposableEmail(email);
                if (isDisposable)
                {
                    disposableEmails.Add(email);
                }
                else
                {
                    badEmails.Add(email);
                }
            }
        }

        // Update counts after validation
        validEmailCount = validEmails.Count;
        badEmailCount = badEmails.Count;
        disposableEmailCount = disposableEmails.Count;

        // Update count labels
        label2.Text = $"Valid Emails: {validEmailCount}";
        label3.Text = $"Bad/Dead Emails: {badEmailCount}";
        label4.Text = $"Disposable Emails: {disposableEmailCount}";

        // Display the emails in the DataGridView
        DisplayEmailsInDataGridView();
    }
    catch (Exception ex)
    {
        MessageBox.Show($"Error validating emails: {ex.Message}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
    }
}

private void DisplayEmailsInDataGridView()
{
    // Clear DataGridView before populating new data
    guna2DataGridView1.Rows.Clear();

    // Determine the maximum count among the different email categories
    int maxCount = Math.Max(Math.Max(validEmails.Count, badEmails.Count), disposableEmails.Count);

    // Ensure that the DataGridView has enough rows to display all the emails
    guna2DataGridView1.Rows.Add(maxCount);

    // Display emails in the respective DataGridView columns
    for (int i = 0; i < maxCount; i++)
    {
        guna2DataGridView1.Rows[i].Cells[0].Value = i < validEmails.Count ? validEmails[i] : ""; // Display in the Valid column (Column Index 0)
        guna2DataGridView1.Rows[i].Cells[1].Value = i < badEmails.Count ? badEmails[i] : ""; // Display in the Bad column (Column Index 1)
        guna2DataGridView1.Rows[i].Cells[2].Value = i < disposableEmails.Count ? disposableEmails[i] : ""; // Display in the Disposable column (Column Index 2)
    }

    // If the counts of emails are unequal, clear the remaining cells in the column
    for (int i = maxCount; i < guna2DataGridView1.Rows.Count; i++)
    {
        guna2DataGridView1.Rows[i].Cells[0].Value = ""; // Clear cell in Valid column
        guna2DataGridView1.Rows[i].Cells[1].Value = ""; // Clear cell in Bad column
        guna2DataGridView1.Rows[i].Cells[2].Value = ""; // Clear cell in Disposable column
    }
}

private async Task<bool> IsDisposableEmail(string email)
{
    string domain = email.Split('@').LastOrDefault();
    if (!string.IsNullOrEmpty(domain))
    {
        var disposableEmailChecker = new DisposableEmailChecker();
        return await disposableEmailChecker.IsDisposableEmailDomain(domain);
    }
    return false; // Return false if domain is empty
}

Troubleshooting Steps

To identify the potential issue causing the disposable email column to not display data properly in the DataGridView, follow these steps:

1. Verify if the disposableEmails list contains the correct email addresses identified as disposable through the IsDisposableEmail() method. This can be done by adding debug statements or using breakpoints to inspect the list.
2. Check if the DisplayEmailsInDataGridView() method is being called after the validation process. Ensure that there are no logical errors or missing calls to this method.
3. Double-check the DataGridView setup, such as column names, column indexes, and any formatting settings. Make sure the Disposable column is correctly mapped to the respective DataGridView column.
4. Review the code that populates the Disposable column in the DataGridView. Check if the conditional statement (i < disposableEmails.Count ? disposableEmails[i] : “”) is functioning as expected.
5. Inspect the DisposableEmailChecker class and its IsDisposableEmailDomain() method. Ensure that the domain extraction logic (email.Split(‘@’).LastOrDefault()) is correct and returning the expected domain for disposable email identification.

Conclusion

By following these troubleshooting steps and reviewing the relevant code snippet, you should be able to identify and resolve the issue with displaying the disposable email column in your C# email validation tool’s DataGridView. Remember to test your code after making any modifications to ensure that it functions as intended. Good luck!