Ajax动态加载<td><select>后下拉框默认选中问题

$.each(data.result,function(i,emp){

                    s='<tr onMouseOut="out(this)" onMouseOver=over(this)>'+

                        '<td>'+emp.employeeName+'</td>'+

                        '<td>'+emp.employTime+'</td>'+

                        '<td>'+emp.organization.organizationName+'</td>'+

                        '<td>'+emp.position+'</td>'+

                        '<td><select id="mySelect">'+

                        '<option value=3>通过</option>'+

                        '<option value=4>入职</option></select></td>'+

                        '<td>'+

                            '<div class="hidden-sm hidden-xs action-buttons">'+

                               ' <a class="blue" onclick=browse(\"'+emp.employeeId+'\")>'+

                                   ' <i class="ace-icon fa fa-search-plus bigger-130"></i>'+

                                '</a>'+

                                ' <a class="green" onclick=update(\"'+emp.employeeId+'\")>'+

                                    '<i class="ace-icon fa fa-pencil bigger-130"></i>'+

                               ' </a>'+

                               ' <a class="red" onclick=del(\"'+emp.employeeId+'\")>'+

                                   ' <i class="ace-icon fa fa-trash-o bigger-130"></i>'+

                               ' </a>'+

                           ' </div>'+

                       ' </td>'+

                    '</tr>';

                    $("#tb").append(s);

                    $("tr:last").find("#mySelect option[value='"+emp.employeeState+"']").attr("selected",true);
                });

  $("tr:last").find("#mySelect option[value='"+emp.employeeState+"']").attr("selected",true); 

每次得到表格的最后一行的下拉框$("tr:last").find("#mySelect option[value='"+emp.employeeState+"']")，比对值相等就选中