仅按日期过滤 Telerik MVC 网格（忽略时间值）

Question

我在 Telerik MVC Grid 中有一个 DateTime 类型的列。我只想使用它的日期部分来显示和过滤。因此，我使用了以下代码

@(Html.Telerik().Grid<State>()
      .Name("tlkStateGrid")
      .Columns(col => {
          col.Bound(m => m.CreatedOn).Title("Created On").Format("{0:dd/MM/yyyy}");

网格确实以指定的格式显示日期（CreatedOn）。但是，过滤并没有按预期工作。我认为在过滤时，网格也会考虑时间值。因此，如果两个日期相同但时间值不同，则它们不被视为“相等”。 如何配置网格以在过滤时忽略时间值并仅比较日期。

注意：我在 Telerik MVC 论坛中发布了类似的问题，但尚未得到答案。

Answer 1

您可以修改 lambda 表达式以将 CreatedOn 属性显式修改为日期。您将仅获得日期时间对象的日期部分。

col.Bound(m => m.CreatedOn.Date)

您的新代码现在如下所示。

@(Html.Telerik().Grid<State>()
      .Name("tlkStateGrid")
      .Columns(col => {
          col.Bound(m => m.CreatedOn.Date).Title("Created On").Format({0:dd/MM/yyyy}");

如果 CreatedOn 是可为空的日期时间，您需要在获取 Date 组件之前访问其 Value 属性。见下文。

col.Bound(m => m.CreatedOn.HasValue? m.CreatedOn.Value.Date : m.CreatedOn)

Answer 2

我创建了以下代码，它改变了日期过滤器的定义方式：

/// <summary>
/// Maps DateTime related filters.
/// * IsEqualTo filter is converted to ('x-date' is GreaterThanOrEqualTo 'SearchDate') AND ('x-date' is LessThan 'SearchDate' + 1 Day)
/// * IsNotEqualTo filter is converted to ('x-date' LessThan 'SearchDate') OR ('x-date' is GreaterThan 'SearchDate' + 1 Day) OR ('x-date' is NULL)
/// * IsLessThanOrEqualTo filter is converted to ('x-date' is LessThan 'SearchDate' + 1 Day)
/// </summary>
/// <param name="copyOfOriginalFilters">A copy from the filters.</param>
/// <param name="newFilters">The new filters</param>
protected void MapDateFilter(ReadOnlyCollection<IFilterDescriptor> copyOfOriginalFilters, IList<IFilterDescriptor> newFilters)
{
    newFilters.Clear();

    foreach (var currentFilter in copyOfOriginalFilters)
    {
        Type t = currentFilter.GetType();

        if (t == typeof(FilterDescriptor))
        {
            var filter = currentFilter as FilterDescriptor;

            if (filter.ConvertedValue.GetType() == typeof(DateTime))
            {
                DateTime datePart = ((DateTime)filter.ConvertedValue).Date;

                if (filter.Operator == FilterOperator.IsEqualTo)
                {
                    var compositeFilter = new CompositeFilterDescriptor();
                    compositeFilter.FilterDescriptors.Add(new FilterDescriptor(filter.Member, FilterOperator.IsGreaterThanOrEqualTo, datePart));
                    compositeFilter.FilterDescriptors.Add(new FilterDescriptor(filter.Member, FilterOperator.IsLessThan, datePart.AddDays(1)));
                    compositeFilter.LogicalOperator = FilterCompositionLogicalOperator.And;

                    newFilters.Add(compositeFilter);
                }
                else if (filter.Operator == FilterOperator.IsNotEqualTo)
                {
                    var compositeFilter = new CompositeFilterDescriptor();
                    compositeFilter.FilterDescriptors.Add(new FilterDescriptor(filter.Member, FilterOperator.IsLessThan, datePart));
                    compositeFilter.FilterDescriptors.Add(new FilterDescriptor(filter.Member, FilterOperator.IsGreaterThan, datePart.AddDays(1)));
                    compositeFilter.FilterDescriptors.Add(new FilterDescriptor(filter.Member, FilterOperator.IsEqualTo, null));
                    compositeFilter.LogicalOperator = FilterCompositionLogicalOperator.Or;

                    newFilters.Add(compositeFilter);
                }
                else if (filter.Operator == FilterOperator.IsLessThanOrEqualTo)
                {
                    newFilters.Add(new FilterDescriptor(filter.Member, FilterOperator.IsLessThan, datePart.AddDays(1)));
                }
                else
                {
                    newFilters.Add(filter);
                }
            }
            else
            {
                newFilters.Add(filter);
            }
        }
        else if (t == typeof(CompositeFilterDescriptor))
        {
            var filter = currentFilter as CompositeFilterDescriptor;

            int numberOfDateFilters = filter.FilterDescriptors.Where(fd =>
                fd is FilterDescriptor &&
                (fd as FilterDescriptor).ConvertedValue != null &&
                (fd as FilterDescriptor).ConvertedValue.GetType() == typeof(DateTime))
                .Count();

            if (numberOfDateFilters == 2)
            {
                var firstFilter = filter.FilterDescriptors[0] as FilterDescriptor;
                firstFilter.Value = ((DateTime)firstFilter.ConvertedValue).Date;

                var secondFilter = filter.FilterDescriptors[1] as FilterDescriptor;
                secondFilter.Value = ((DateTime)secondFilter.ConvertedValue).Date;
            }
            else
            {
                MapDateFilter(new List<IFilterDescriptor>(filter.FilterDescriptors).AsReadOnly(), filter.FilterDescriptors);
            }

            newFilters.Add(filter);
        }
    }
}

可以像这样使用：

protected void MapGridCommand(GridCommand command)
{
    this.MapDateFilter(new List<IFilterDescriptor>(command.FilterDescriptors).AsReadOnly(), command.FilterDescriptors);
}