ant-design-blazor/components/menu/AntSubMenu.razor

@namespace AntBlazor
@inherits AntSubMenuBase

    <CascadingValue Value=this>
        <li nz-submenu class="@ClassMapper.Class" @ref="Ref" style="@Style" @attributes="Attributes" Id="@Id">
            <div class="@TitleDivClass.Class" style="@titleStyle"
                 @onmouseover="()=>SetMouseEnterState(true)"
                 @onmouseout="()=>SetMouseEnterState(false)"
                 @onclick="()=> ClickSubMenuTitle()">
                @if (nzIcon != null)
                {
                    <AntIcon type="@nzIcon"></AntIcon>
                }
                @*<ng-container *nzStringTemplateOutlet="nzTitle">*@
                <span>@((MarkupString)nzTitle)</span>
                @*</ng-container>*@
                @*<ng-content select="[title]" *ngIf="!nzTitle"></ng-content>*@

                @if (Menu.isInDropDown)
                {
                    <span class="ant-dropdown-menu-submenu-arrow">
                        <AntIcon type="right" class="anticon-right ant-dropdown-menu-submenu-arrow-icon"></AntIcon>
                    </span>
                }
                else
                {
                    <i class="ant-menu-submenu-arrow"></i>
                }
            </div>
            @if (Menu.nzMode == NzDirectionVHIType.inline)
            {
                <ul class="@nzMenuClassName ant-menu ant-menu-inline ant-menu-sub" style="transition: height 0.5s; @submenuStyle">
                    @ChildContent
                </ul>
            }
            </li>

            @if (nzOpen && Menu.nzMode != NzDirectionVHIType.inline)
            {
                <div style="position: absolute; top: 0px; left: 0px; width: 100%;">
                <div class="ant-menu-submenu ant-menu-submenu-popup @PopupClassMapper.Class"
                     style="left:@(element.offsetLeft+element.clientWidth+10)px; top:@(element.offsetTop)px; @(isMouseHover?"":"display: none;")"
                     @onmouseout="()=>SetMouseEnterState(false)"
                     @onmouseover="()=>SetMouseEnterState(true)">
                    <ul class="@nzMenuClassName @PopupUlClassMapper.Class ant-menu-submenu-content" style="@(isMouseHover?"":"display: none;")">
                        @ChildContent
                    </ul>
                </div>
            </div>
        }
    </CascadingValue>

@inject JsInterop.JsInterop js
@code {

    string titleStyle => Menu.nzMode == NzDirectionVHIType.inline ?
        $"padding-left:{(nzPaddingLeft ?? Level * Menu.nzInlineIndent)}px" : "";

    string submenuStyle => nzOpen ? "" : "height: 0px; overflow: hidden;";

    protected override void OnInitialized()
    {
        base.OnInitialized();
        TitleDivClass
            .If("ant-dropdown-menu-submenu-title", () => Menu.isInDropDown)
            .If("ant-menu-submenu-title", () => !Menu.isInDropDown)
            ;

    }

}