Ajaxtoolkit-当我点击

Question

我已经尝试了一切，但没有任何效果，我现在不知道了。我使用了一个示例，该示例曾经可以工作，但现在不再使用。我用这个例子

1. https://www.aspsnippets.com/Articles/AJAX-AutoCompleteExtender-Example-in-ASPNet.aspx

然后从此处下载ajaxtoolkit

1. https://www.devexpress.com/products/ajax-control-toolkit/

我在页面顶部有scriptmanager，它看起来像这样。

这是我的代码

Masterpage.master

<asp:TextBox ID="txtContactsSearch" aria-describedby="basic-addon2" class="form-control-header" placeholder="Søg her ..." runat="server"></asp:TextBox> <cc1:AutoCompleteExtender ServiceMethod="SearchCustomers" MinimumPrefixLength="2" ServicePath="MasterPage.master"  CompletionInterval="100" EnableCaching="false" CompletionSetCount="10" TargetControlID="txtContactsSearch"  ID="AutoCompleteExtender1" runat="server" FirstRowSelected = "false"></cc1:AutoCompleteExtender>

我的代码隐藏

 [System.Web.Script.Services.ScriptMethod()]
[System.Web.Services.WebMethod]
public static List<string> SearchCustomers(string prefixText, int count)
{
    using (MySqlConnection conn = new MySqlConnection())
    {
        conn.ConnectionString = ConfigurationManager.ConnectionStrings["Connectionstring"].ConnectionString;
        using (MySqlCommand cmd = new MySqlCommand())
        {
            cmd.CommandText = "select Produktnavn from Produkter where " +
            "Produktnavn like @SearchText + '%'";
            cmd.Parameters.AddWithValue("@SearchText", prefixText);
            cmd.Connection = conn;
            conn.Open();
            List<string> customers = new List<string>();
            using (MySqlDataReader sdr = cmd.ExecuteReader())
            {
                while (sdr.Read())
                {
                    customers.Add(sdr["Produktnavn"].ToString());
                }
            }
            conn.Close();
            return customers;
        }
    }
}