How to sort a listview column that contains file size data? C#

Question

I want to sort the items inside column of ListView, i already made it, but... i can\'t made it with the type of data in column (see picture), someone knows the way for do it

Answer 1

Create listViewSizeSorter class extending Icomparer interface as below.

using System.Collections;
using System.Windows.Forms;

namespace MyNameSpace
{
    /// 

    /// This class is an implementation of the 'IComparer' interface.
    /// 
    public class ListViewSizeSorter : IComparer
    {
        /// 

        /// Specifies the column to be sorted
        /// 
        private int _columnToSort;
        /// 

        /// Specifies the order in which to sort (i.e. 'Ascending').
        /// 
        private SortOrder _orderOfSort;

        /// 

        /// Class constructor.  Initializes various elements
        /// 
        public ListViewSizeSorter()
        {
            // Initialize the column to '0'
            SortColumn = 0;

            // Initialize the sort order to 'none'
            Order = SortOrder.None;
        }

        /// 

        /// This method is inherited from the IComparer interface.  It compares the two objects passed using a case insensitive comparison.
        /// 
        /// First object to be compared
        /// Second object to be compared
        /// The result of the comparison. "0" if equal, negative if 'x' is less than 'y' and positive if 'x' is greater than 'y'
        public int Compare(object x, object y)
        {
            var listviewX = (ListViewItem)x;
            var listviewY = (ListViewItem)y;
            string strX = listviewX.SubItems[_columnToSort].Text;
            string strY = listviewY.SubItems[_columnToSort].Text;

            // Nulls first (null means less, since it's blank)
            if (strX == null)
            {
                if (strY == null)
                    return 0;
                return -1;
            }
            if (strY == null)
                return 1;

            // Convert the non-KB part to a number
            double numX = 0;
            double numY = 0;
            if (strX.EndsWith("KB") || strX.EndsWith("GB") || strX.EndsWith("MB"))
                double.TryParse(strX.Substring(0, strX.Length - 3), out numX);
            if (strX.EndsWith("Bytes"))
                double.TryParse(strX.Substring(0, strX.Length - 6), out numX);
            if (strY.EndsWith("KB") || strY.EndsWith("GB") || strY.EndsWith("MB"))
                double.TryParse(strY.Substring(0, strY.Length - 3), out numY);
            if (strY.EndsWith("Bytes"))
                double.TryParse(strX.Substring(0, strY.Length - 6), out numY);
            long bytesX;
            long bytesY;
            if (strX.EndsWith("KB"))
                bytesX = (long)numX * 1024;
            else if (strX.EndsWith("MB"))
                bytesX = (long)numX * 1048576;
            else if (strX.EndsWith("GB"))
                bytesX = (long)numX * 1073741824;
            else
                bytesX = (long) numX;

            if (strY.EndsWith("KB"))
                bytesY = (long)numY * 1024;
            else if (strY.EndsWith("MB"))
                bytesY = (long)numY * 1048576;
            else if (strY.EndsWith("GB"))
                bytesY = (long)numY * 1073741824;
            else
                bytesY = (long) numY;

            var compareResult = bytesX.CompareTo(bytesY);

            if (_orderOfSort == SortOrder.Ascending)
            {
                // Ascending sort is selected, return normal result of compare operation
                return compareResult;
            }
            if (_orderOfSort == SortOrder.Descending)
            {
                // Descending sort is selected, return negative result of compare operation
                return (-compareResult);
            }
            // Return '0' to indicate they are equal
            return 0;
        }

        /// 

        /// Gets or sets the number of the column to which to apply the sorting operation (Defaults to '0').
        /// 
        public int SortColumn
        {
            set
            {
                _columnToSort = value;
            }
            get
            {
                return _columnToSort;
            }
        }

        /// 

        /// Gets or sets the order of sorting to apply (for example, 'Ascending' or 'Descending').
        /// 
        public SortOrder Order
        {
            set
            {
                _orderOfSort = value;
            }
            get
            {
                return _orderOfSort;
            }
        }
    }
}

Change namespace name with yours.

Add following line in your form.

private readonly ListViewSizeSorter _listViewSizeSorter;
        public Form1()
        {
            InitializeComponent();
            _listViewSizeSorter = new ListViewSizeSorter {SortColumn = 1};
        }

private void ListViewFilesColumnClick(object sender, ColumnClickEventArgs e)
        {
            // Determine if clicked column is already the column that is being sorted.
            if (e.Column == _listViewColumnSorter.SortColumn)
            {
                if(e.Column.Equals(1))
                {
                    listViewFiles.ListViewItemSorter = _listViewSizeSorter;
                    // Reverse the current sort direction for this column.
                    _listViewSizeSorter.Order = _listViewSizeSorter.Order == SortOrder.Ascending ? SortOrder.Descending : SortOrder.Ascending;
                }
            }
            else
            {
                // Set the column number that is to be sorted; default to ascending.
                _listViewColumnSorter.SortColumn = e.Column;
                _listViewColumnSorter.Order = SortOrder.Ascending;
            }

            // Perform the sort with these new sort options.
            listViewFiles.Sort();
        }