Question

我在我的CSharp工具中使用这个SortableBindingList对DataGridView中的项目进行排序，除了十进制数字作为字符串之外，它工作正常，例如“125.03”！

public class SortableBindingList<T> : BindingList<T>
{
    private ArrayList sortedList;
    private bool isSortedValue;

    public SortableBindingList()
    {
    }

    public SortableBindingList(IList<T> list)
    {
        foreach (object o in list)
        {
            this.Add((T)o);
        }
    }

    protected override bool SupportsSortingCore
    {
        get { return true; }
    }


    protected override bool IsSortedCore
    {
        get { return isSortedValue; }
    }

    ListSortDirection sortDirectionValue;
    PropertyDescriptor sortPropertyValue;

    protected override void ApplySortCore(PropertyDescriptor prop,
        ListSortDirection direction)
    {
        sortedList = new ArrayList();

        Type interfaceType = prop.PropertyType.GetInterface("IComparable");

        if (interfaceType == null && prop.PropertyType.IsValueType)
        {
            Type underlyingType = Nullable.GetUnderlyingType(prop.PropertyType);

            if (underlyingType != null)
            {
                interfaceType = underlyingType.GetInterface("IComparable");
            }
        }

        if (interfaceType != null)
        {
            sortPropertyValue = prop;
            sortDirectionValue = direction;

            IEnumerable<T> query = base.Items;
            if (direction == ListSortDirection.Ascending)
            {
                query = query.OrderBy(i => prop.GetValue(i));
            }
            else
            {
                query = query.OrderByDescending(i => prop.GetValue(i));
            }
            int newIndex = 0;
            foreach (object item in query)
            {
                this.Items[newIndex] = (T)item;
                newIndex++;
            }
            isSortedValue = true;
            this.OnListChanged(new ListChangedEventArgs(ListChangedType.Reset, -1));

        }
        else
        {
            throw new NotSupportedException("Cannot sort by " + prop.Name +
                ". This" + prop.PropertyType.ToString() +
                " does not implement IComparable");
        }
    }

    protected override PropertyDescriptor SortPropertyCore
    {
        get { return sortPropertyValue; }
    }

    protected override ListSortDirection SortDirectionCore
    {
        get { return sortDirectionValue; }
    }

}

链接：DataGridView Using SortableBindingList

哪些适应性是必要的？

感谢您的帮助！

Answer 1

可能的解决方案：

decimal value;
if (direction == ListSortDirection.Ascending)
{
    // check if element count is not 0 and value is decimal
    if (query.Count() > 0 &&
        decimal.TryParse(prop.GetValue(query.ElementAt<T>(0)).ToString(), NumberStyles.Any, CultureInfo.InvariantCulture, out value))
    {
        // convert to decimal and sort
        query = query.OrderBy(i => Convert.ToDecimal(prop.GetValue(i)));
    }
    else query = query.OrderBy(i => prop.GetValue(i));
}
else
{
    if (query.Count() > 0 &&
        decimal.TryParse(prop.GetValue(query.ElementAt<T>(0)).ToString(), NumberStyles.Any, CultureInfo.InvariantCulture, out value))
    {
        query = query.OrderByDescending(i => Convert.ToDecimal(prop.GetValue(i)));
    }
    else query = query.OrderByDescending(i => prop.GetValue(i));
}

DataGridView SortableBindingList为十进制数字作为字符串

1 个答案: