//Model
public class TestFormModelClass
{
  public int[] MonthsSelectedIds { get; set; }
}

//View
@model TestFormModelClass

<form method="post">
  <kendo-dropdowntree for="MonthsSelectedIds" 
      check-all="true"
      datatextfield="Month"
      datavaluefield="Id">
      <hierarchical-datasource type="DataSourceTagHelperType.Custom">
                <schema>
                    <hierarchical-model id="id"></hierarchical-model>
                </schema>
                <transport>
                    <read url="/api/items" />
                </transport>
      </hierarchical-datasource>
      <checkboxes check-children="false" name="CheckedMonths" enabled="true" />
  </kendo-dropdowntree>

  <button type="submit">Save</button>
</form>

  <script>
    function contains(parent, child) {
        try {
            return $.contains(parent, child);
        } catch (e) {
            return false;
        }
    }

    kendo.ui.ContextMenu.fn.open = function (x, y) {
        var OPEN = "open",
            ACTIVATE = "activate",
            DOCUMENT_ELEMENT = $(document.documentElement),
            NS = ".kendoMenu";
        var that = this;

        x = $(x)[0];

        if (contains(that.element[0], $(x)[0]) || that._itemHasChildren($(x))) { // call parent open for children elements
            kendo.ui.Menu.fn.open.call(that, x);
        } else {
            if (that._triggerEvent({ item: that.element, type: OPEN }) === false) {
                if (that.popup.visible() && that.options.filter) {
                    that.popup.close(true);
                    that.popup.element.parent().kendoStop(true);
                }

                if (!that._triggerFocusOnActivate) {
                    that._triggerFocusOnActivate = that._focusMenu.bind(that);
                }
                that.bind(ACTIVATE, that._triggerFocusOnActivate);
                if (y !== undefined) {
                    var overflowWrapper = that._overflowWrapper();
                    if (overflowWrapper) {
                        var offset = overflowWrapper.offset();
                        x -= offset.left;
                        y -= offset.top;
                    }
                    that.popup.wrapper.hide();
                    that._configurePopupScrolling(x, y);
                    that.popup.open(x, y);
                } else {
                    that.popup.options.anchor = (x ? x : that.popup.anchor) || that.target;
                    that.popup.element.parent().kendoStop(true);
                    that._configurePopupScrolling();
                    that.popup.open();
                }

                DOCUMENT_ELEMENT.off(that.popup.downEvent, that.popup._mousedownProxy);
                DOCUMENT_ELEMENT
                    .on(kendo.support.mousedown + NS + that._marker, that._closeProxy);
            }
        }

        return that;
    };
</script>

/* 5.7.3 - Filemanager Image Grid View */
.FileManagerImgGridView {
    display: flex;
    justify-content: start;
    align-items: center;
    gap: 10px;
    cursor: zoom-in;
}
/* 5.7.4 - Filemanager Image List View */
.FileManagerImgListView {
    cursor: zoom-in;
    max-width: 115px;
    box-shadow: 0 0 10px rgba(0,0,0,0.4);
    transition-duration: .5s;
}

    .FileManagerImgListView:hover {
        transition-duration: .5s;
        transform: translateY(5px) scale(1.75);
        border-radius: 3px;
        z-index: 100;
    }

/* 5.7.5 - Filemanager Image Detail */
.FileManagerImgDetail {
    max-height: 280px;
    max-width: 280px;
    border-radius: 5px;
    box-shadow: 0 0 20px rgba(0,0,0,0.4);
    cursor: pointer;
    transition-duration: .5s;
}

    .FileManagerImgDetail:hover {
        transition-duration: .5s;
        transform: scale(1.2);
        max-width: 80%;
        border-radius: 50%;
        box-shadow: 0 0 20px rgba(0,0,0,0.4);
    }

.FileManagerImgDownloadLink {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-left: 10px;
    padding: 5px 10px;
    border-radius: 10px;
    color: var(--bs-primary-inverted);
    background-color: var(--bs-primary);
    box-shadow: 0 0 10px rgba(0 0 0 /.7);
    gap: 5px;
}

    .FileManagerImgDownloadLink a {
        text-decoration: none;
        color: var(--bs-primary-inverted);
    }

using SixLabors.ImageSharp;
using SixLabors.ImageSharp.Processing;

public virtual IActionResult Thumbnail(string path)
    {
        var virtualPath = Path.Combine(_thumbnailFolderRoot);
        var physicalPath = Path.Combine(ConstantVar.webEnv.WebRootPath, virtualPath.Replace('/', '\\'));
        path = Path.Combine(physicalPath, path);
        FileInfo imageInfo = new FileInfo(path);

        int width = 75;
        int height = 75;
        bool KeepRatio = true;

        using (Image image = Image.Load(imageInfo.FullName))
        {

            // Figure out the ratio
            double ratioX = (double)width / (double)image.Width;
            double ratioY = (double)height / (double)image.Height;
            // use whichever multiplier is smaller
            double ratio = ratioX < ratioY ? ratioX : ratioY;

            int newHeight = height;
            int newWidth = width;

            if (KeepRatio)
            {
                // now we can get the new height and width
                newHeight = Convert.ToInt32(image.Height * ratio);
                newWidth = Convert.ToInt32(image.Width * ratio);
            }

            image.Mutate(s => s.Resize(width: newWidth, height: newHeight));
            using (var ms = new MemoryStream())
            {
                image.SaveAsJpeg(ms);
                return File(ms.ToArray(), "image/jpg");
            }
        }
    }

.Events(e=>e.Edit("ganttEdit"))

<script>
    function ganttEdit(e){
       var tabstrip = 
       e.container.find(".k-gantt-edit-tabstrip").data().kendoTabStrip;
       tabstrip.bind("activate",function(args){
           if(args.item.textContent == "Other")
           {
              var otherForm = $(".k-gantt-form-other").data().kendoForm;
              var newOptions = otherForm.options;
              
              if(newOptions.items.length < 3)
              {
              newOptions.items.push({
                "field": "Role",
                "type": "string",
               "defaultValue": ""
               });

              otherForm.setOptions(newOptions);
              }
           }
       })
    }
</script>