C# 中对 ArrayList 的排序

//目录条目类
public class FolderItem
{
    public string filename;
    public string filetype;
    public int size;
    public int number;
    public FolderItem(string filename, string filetype, int size, int number)
    {
        this.filename = filename;
        this.filetype = filetype;
        this.size = size;
        this.number = number;
    }
    
}

//目录上传时间排序
public class FolderItemCompare : IComparer
{
    public int Compare(object manA, object manB)
    {
        FolderItem man1 = (FolderItem)manA;
        FolderItem man2 = (FolderItem)manB;
        return man1.number.CompareTo(man2.number);
    }
}

ArrayList arrList = new ArrayList();
arrList.Add(item);
//...
arrList.Sort(new FolderItemCompare());