ASP.Net 核心 - 如何在不刷新的情况下发送消息以从控制器查看?

ASP.Net Core - How to send message to view from controller without refreshing?

我想在不刷新的情况下显示来自控制器的自定义 success/error 消息。
我试过了,但看起来需要刷新页面才能显示数据:

观点:

@if (ViewBag.Message != null)
{
   <span>@ViewBag.Message</span>
}

控制器:

if (CurrentOrgLevel < MaxOrgLevel)
        {
            if (ModelState.IsValid && CurrentOrgLevel < MaxOrgLevel)
            {
                orgStructure.Insert(org, ModelState);
            }
        }
        else
        {
            ViewBag.Message = "Error: Max level reached.";
        }

这是由 telerik 控件树列表 add child 事件触发的:https://demos.telerik.com/aspnet-core/treelist/editing

树列表:

@(Html.Kendo().TreeList<OCIT.Data.Models.OrgStructure>()
            .Name("treelist")
            .Toolbar(toolbar => toolbar.Create().Text("Add " + sessionUser.Level1Name))
            .Columns(columns =>
            {
                columns.Add().Field(e => e.LevelName).Width(40);
                columns.Add().Field(e => e.Name).Width(100);
                columns.Add().Field(e => e.Level).Width(26);
                columns.Add().Width(100).Command(c =>
                {
                    c.CreateChild().Text("Add child");
                    c.Edit();
                    c.Destroy();
                })
                        .HtmlAttributes(new {style = "text-align: center;"});
            })
            .Editable()
            .Sortable()
            .Filterable()
            .DataSource(dataSource => dataSource
                .Create(create => create.Action("Create", "OrgStructure"))
                .Read(read => read.Action("All", "OrgStructure").Data("treelistParam"))
                .Update(update => update.Action("Update", "OrgStructure"))
                .Destroy(delete => delete.Action("Destroy", "OrgStructure"))
                .ServerOperation(false)
                .Model(m =>
                {
                    m.Id(f => f.NodeId);
                    m.ParentId(f => f.ParentNodeId).DefaultValue(sessionUser.DepartmentId);
                    m.Field(f => f.FiscalYear).DefaultValue(sessionUser.CurrentFiscalYearId);
                    m.Field(f => f.CreatedDateTime);
                    m.Field(f => f.DepartmentCode);
                    m.Field(f => f.Acronym);
                    m.Field(f => f.DepartmentId).DefaultValue(sessionUser.DepartmentId);
                    m.Field(f => f.RequiresChildSelect);
                    m.Expanded(false);
                    m.Field(f => f.Name);
                    m.Field(f => f.Level).Editable(false);
                    m.Field(f => f.LevelName).Editable(false);
                    m.Field(f => f.ParentNodeId);
                })

            )
            .Height(505)
.Events(events =>
{
    events.FilterMenuOpen("onFilterMenuOpen");
    events.DataBound("dataBound");
    events.DataBinding("dataBinding");
    events.Save("onSave");
    events.Remove("saveExpandState");
    events.Cancel("onCancel");
})
)

点击add child时,触发onSave javascript函数:

function onSave() {

}

我相信我们需要 Ajax,但是在 treelist 控件已经处理 ajax post 的情况下如何实现它,但是我们需要自定义 postback?

我需要在不重新加载的情况下显示错误,treelist 控件在数据源中有一个错误处理程序 .Events(ev=>ev.Error("onError")):

.DataSource(dataSource => dataSource
     .Create(create => create.Action("Create", "OrgStructure"))
     .Read(read => read.Action("All", "OrgStructure").Data("treelistParam"))
     .Update(update => update.Action("Update", "OrgStructure"))
     .Destroy(delete => delete.Action("Destroy", "OrgStructure"))
   .Events(ev=>ev.Error("onError"))
     .ServerOperation(false)
     .Model(m =>
     {
         m.Id(f => f.NodeId);
         m.ParentId(f => f.ParentNodeId).DefaultValue(sessionUser.DepartmentId);
         m.Field(f => f.FiscalYear).DefaultValue(sessionUser.CurrentFiscalYearId);
         m.Field(f => f.CreatedDateTime);
         m.Field(f => f.DepartmentCode);
         m.Field(f => f.Acronym);
         m.Field(f => f.DepartmentId).DefaultValue(sessionUser.DepartmentId);
         m.Field(f => f.RequiresChildSelect);
         m.Expanded(false);
         m.Field(f => f.Name);
         m.Field(f => f.Level).Editable(false);
         m.Field(f => f.LevelName).Editable(false);
         m.Field(f => f.ParentNodeId);
     })

 )