C#

/// <summary>
/// Deletes a Role.
/// </summary>
/// <param name="id">The Role id.</param>
public void DeleteRole(int id)
{
    try
    {
        var role = (from u in dataContext.Roles
                    where u.Id == id
                    select u).FirstOrDefault();
        var hasUsers = (from u in dataContext.Users
                        where u.RoleId == id
                        select u).Any();
        if (hasUsers)
        {
            //<==== THIS SHOULD BE SEEN BY THE USER
            throw new Exception($"The role '{role.RoleName}' cannot be deleted because it has users assigned to it." );
        }
        else
        {
            if (role != null)
            {
                role.IsDeleted = true;
                dataContext.SubmitChanges();
            }
        }
    }
    catch (Exception)
    {
        //<==== IF HERE, SOMETHING ELSE WENT WRONG, SO LET THE GLOBAL 
        //      EXCEPTION HANDLER HANDLE IT
        throw;  
    }
}

 <span id ="long"></span>
<script type='text/javascript' id="weather-link" src='https://darksky.net/widget/default/></script>
    <script>const weatherLink = $("#weather-link");
    weatherLink.html("<span id=\"" + response.latitude + "," +response.longitude + "\">/uk12/de.js?width=100%&height=350&title=Basel&textColor=333333&bgColor=FFFFFF&transparency=false&skyColor=undefined&fontFamily=Default&customFont=&units=uk&htColor=333333<Color=333333&displaySum=yes&displayHeader=yes</span>");
    weatherLink.attr("src", weatherLink.attr("src") + response.city);</script>

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script>

          $("#long").html(response.latitude   + ", " + response.longitude );

    $("#response").html(JSON.stringify(response, null, 4));
  }, "jsonp");
</script>

<pre><div size="10" id="para1"></div>  <p></p><asp:Label ID="Label2" runat="server" Text="" Font-Size="XX-Large"></asp:Label><p></p><asp:Label ID="Label3" runat="server" Text="" Font-Size="XX-Large"></asp:Label>

<script>
document.getElementById("para1").innerHTML = formatAMPM();

    function formatAMPM() {
        var d = new Date(),

            days = ['sonday', 'monday', 'tuesday', 'Mittwoch', 'Donnerstag', 'Freitag', 'Samstag'];
        return days[d.getDay()];
    }</script>

HtmlDocument page = new HtmlWeb().Load(@"D:\Downloads\wichtig\try\WebApplication1-Kopie-Kopie\MeineWebseite\löschen\WebForm2.aspx");
        var title = page.DocumentNode.SelectSingleNode("//div[@id='para1']");
        Label3.Text = title.ToString();

document2.Load(@"D:\Downloads\wichtig\try\WebApplication1-Kopie-Kopie\MeineWebseite\löschen\WebForm2.aspx");

        string tag = document2.GetElementbyId("para1").Name;
        Label2.Text = tag;

<div>id="para1</div>