将所选值 Id 从父级传递给子级 Kendo DropdownList

Question

我有一个使用 jquery 和 Kendo UI 的级联 Kendo DropdownList。我的问题是我想将选定的值 Id 从父级传递给子级，这意味着将 StateId 传递给城市 DropdownList 并根据选定的 StateId 过滤城市但是当我尝试调试它时我遇到了一些奇怪的事情，即 StateId 为空。有没有人可以帮助我？谢谢。

   [HttpPost]
       public async Task<JsonResult> GetCities(DataSourceRequest request, CancellationToken cancellationToken = default)
        {
            request.Skip = 0;
            request.Take = 2000;

            var city = await _cityService.GetCities(request, cancellationToken);

            return Json(city);
        }

如您所见，该值为空，这是我的 jquery 部分代码...

 $("#drpState").kendoDropDownList({
                optionLabel: "States...",
                delay: 10,
                dataTextField: "Name",
                dataValueField: "StateId",
                dataSource: {
                    type: "json",
                    serverFiltering: true,
                    transport: {
                        read: {
                            headers: {
                                "__RequestVerificationToken": $('input[name=__RequestVerificationToken]').val()
                            },
                            type: "Post",
                            dataType: "json",
                            url: "/Supervision/Tracking/GetStates",
                        }
                    },
                    schema: { data: 'Data' }
                },
            }).data("kendoDropDownList");


            $("#drpCity").kendoDropDownList({
                cascadeFrom: "drpState",
                optionLabel: "Cities...",
                delay: 10,
                dataTextField: "Name",
                dataValueField: "CityId",
                autoBind: false,
                dataSource: {
                    type: "json",
                    serverFiltering: true,
                    transport: {
                        read: {
                            headers: {
                                "__RequestVerificationToken": $('input[name=__RequestVerificationToken]').val()
                            },
                            type: "Post",
                            dataType: "json",
                            url: "/Supervision/Tracking/GetCities"
                        }
                    },
                    schema: { data: 'Data' }

                }
            }).data("kendoDropDownList");

Answer 1

when I tried to debug it I faced something weird which was that the StateId is null.

我使用 Kendo UI jQuery DropDownList 和 ASP.NET 核心 WebAPI 作为后端服务进行了测试，我可以重现同样的问题。

根据JS客户端发出的请求的formdata，ASP.NET核心端点可以很好地接受和处理这些数据，您可以尝试以下解决方法。

自定义模型类

public class DataSourceRequestForCore
{
    public int Take { get; set; }
    public int Skip { get; set; }
    public FilterForCore filter { get; set; }
}

public class FilterForCore
{
    public string logic { get; set; }
    public List<FilterEntry> filters { get; set; }
}

public class FilterEntry
{
    [DataMember(Name = "field")]
    public string Field { get; set; }

    [DataMember(Name = "operator")]
    public string Operator { get; set; }

    [DataMember(Name = "value")]
    public string Value { get; set; }
}

操作方法

[HttpPost]
public async Task<JsonResult> GetCities(DataSourceRequestForCore request, CancellationToken cancellationToken = default)
{
    request.Skip = 0;
    request.Take = 2000;

    //....
    //code logic here

测试结果

将所选值 Id 从父级传递给子级 Kendo DropdownList

pass selected value Id from parent to child Kendo DropdownList

javascript

jquery

kendo-ui

asp.net-core