using System;

using System.Text.RegularExpressions;

​

public class Program

{

    public static void Main()

    {

        string html = "<p style=\"text-align: center; \"><img src=\"https://resources.globalair.com/images/article/Falcon6X_Rollout_04.jpg?w=800\"><br><img src=\"https://resources.globalair.com/images/article/Another_Image.jpg\"><br></p>";

​

        string updatedHtml = AddAltTagsToImages(html);

​

        Console.WriteLine(updatedHtml);

    }

​

    static string AddAltTagsToImages(string html)

    {

        // Define a regular expression pattern to match <img> tags without alt attribute

        string pattern = "<img\\s+[^>]*?src=\"([^\"]+)\"[^>]*?>";

​

        // Use a MatchEvaluator delegate to replace matched img tags with alt attribute

        string updatedHtml = Regex.Replace(html, pattern, match =>

        {

            // Extract the image file name from the src attribute

            string src = match.Groups[1].Value;

            string imageName = GetImageNameFromUrl(src);

​

            // Construct the updated img tag with the alt attribute

            string updatedImgTag = "<img src=\"" + src + "\" alt=\"" + imageName + "\">";

            return updatedImgTag;

        });

​

        return updatedHtml;

    }

​

    static string GetImageNameFromUrl(string url)

    {

        // Split the URL by '/'

        string[] parts = url.Split('/');

        // Get the last part of the URL (should be the image file name)

        string imageName = parts[parts.Length - 1];

​

        // Remove any query parameters if present

        int queryIndex = imageName.IndexOf('?');

        if (queryIndex != -1)

        {

            imageName = imageName.Substring(0, queryIndex);

        }

​

        return imageName;

    }

}

​