<select id="slroles" ng-model="vm.usersetting.edt_roles" class="form-control select2"  multiple="multiple">
</select>

 function (response) {
                    
                    that.roles = response.data.DataSet.Body[0];
                    that.edt_roles = response.data.DataSet.Body[1];
                 
                    $("#slroles").select2({
                        data: that.roles
                    });

　　　　　　　　　　　　//主要写法
                    $('#slroles').val(that.edt_roles.split(','));
                    $('#slroles').trigger('change.select2');

                    $("#userEdit").modal("show");
}