Getting ID of embedded ASP Object using JavaScript and jQuery

$(document).ready(function() //when DOM is ready, run containing code
{
  <% if (grvTimeSheets.EditIndex > -1) {%>
      $(#<%=grvTimeSheets.Rows[grvTimeSheets.EditIndex].FindControl("ddlClients").ClientID %>).change(function() {
           $(#<%= grvTimeSheets.ClientID %>).block({ message: null }
        });
}
);
 <% } %>

<script type="text/javascript" src="jquery.js"></script>
 <script type="text/javascript" src="jquery.tablesorter.js"></script>
 <script type="text/javascript" src="jquery.blockUI.js"></script>
 <script type="text/javascript">
$(document).ready(function() //when DOM is ready, run containing code
 {

 }
 );
</script>

<script type="text/javascript" src="jquery.js"></script>
 <script type="text/javascript" src="jquery.tablesorter.js"></script>
 <script type="text/javascript" src="jquery.blockUI.js"></script>
 <script type="text/javascript">
$(document).ready(function() //when DOM is ready, run containing code
{<% if (grvTimeSheets.EditIndex > -1) {%>
  var id = '#<%=grvTimeSheets.Rows[grvTimeSheets.EditIndex].FindControl("ddlClients").ClientID %>';
  $(id).change(function() {
       $(id).block({ message: null }
    });
 <% } %>
}
);
</script>

DropDownList ddl (DropDownList)grvTimeSheets.Rows[grvTimeSheets.EditIndex].FindControl("ddlClients");
 if (ddl != null)
 {
     ClientScriptManager csm = Page.ClientScript;
     Type cstype = this.GetType();
     String csname1 = "PopupScript";

      string script = @"
      <script language='javascript' type='text/javascript'>
      $(#" + ddl.ClientID + ").change(function() { $(" + grvTimeSheets.ClientID + ").blockUI({ message: null }});} </script>";
            csm.RegisterStartupScript(cstype, csname1, script, true);

  }

$(document).ready(function() //when DOM is ready, run containing code
{
  <% if (grvTimeSheets.EditIndex > -1) {%>
      var id = '#<%=grvTimeSheets.Rows[grvTimeSheets.EditIndex].FindControl("ddlClients").ClientID %>';
      $(id).change(function() {
           $(id).block({ message: null }
        });
 <% } %>
}
);

string script = @"<script type=text/javascript> var myControlId = '" + ddl.ClientId  "';") + "</script>"

$(function() {
    $("select.yourMarkerClass").change(....);
});

$('[id$=ddlClients]')

DropDownList ddl = (DropDownList)grvTimeSheets.Rows[grvTimeSheets.EditIndex].FindControl("ddlClients");
        if (ddl != null)
        {
            ClientScriptManager csm = Page.ClientScript;
            Type cstype = this.GetType();
            String csname1 = "PopupScript";


            string script = @"
       <script language='javascript' type='text/javascript'>
       jQuery(#" + ddl.ClientID + ").change(function() { $(" + grvTimeSheets.ClientID + ").blockUI({ message: null }});} </script>";
            csm.RegisterStartupScript(cstype, csname1, script, false);