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c# - How do you use the MySql IN clause

I am trying to figure out how to use the MySql In cluse with ASP.NET C#. Here is my code

var WebSites = string.Join(",", wsl.Select(x => "'" + x.DomainUrl + "'").ToArray());
string q = "select Id, Url, Title, Date, ImageUrl from post where WebSiteUrl IN (@Url)";

When I dont use parameters this code works. When I include parameters I get no results from the query.

Here is my code for parameters

cmd.Parameters.Add("@Urls", MySqlDbType.Text).Value = WebSites;

here is whole code

 public static IList<Post> FindPostsByWebSiteList(IEnumerable<WebSite> wsl)
 {
        var pl = new List<Post>();
        var WebSites = string.Join(",", wsl.Select(x => "'" + x.DomainUrl + "'").ToArray());
        string q = "select Id, Url, Title, Date, ImageUrl from post where WebSiteUrl IN (@Urls)";

        using (MySqlConnection con = new MySqlConnection(WebConfigurationManager.ConnectionStrings["MySqlConnectionString"].ToString()))
        {
            using (MySqlCommand cmd = new MySqlCommand(q, con))
            {
                cmd.Parameters.Add("@Urls", MySqlDbType.Text).Value = WebSites;
                con.Open();

                var reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                while (reader.Read())
                {
                    var p = new Post();
                    p.Id = reader.GetInt32("Id");
                    p.Url = reader.GetString("Url");
                    p.Title = reader.GetString("Title");
                    p.Date = reader.GetDateTime("Date");
                    p.ImageUrl = reader.GetString("ImageUrl");
                    pl.Add(p);
                }
                return pl;
            }
        }
    }
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by (71.8m points)

You have referenced @Url instead of @Urls

maybe just a typo in your question though


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