/// <summary>
/// This method is inherited from the IComparer interface. It compares the two objects passed using a case insensitive comparison.
/// </summary>
/// <param name="x">First object to be compared</param>
/// <param name="y">Second object to be compared</param>
/// <returns>The result of the comparison. "0" if equal, negative if 'x' is less than 'y' and positive if 'x' is greater than 'y'</returns>
public int Compare(object x, object y)
{
int compareResult = 0;
ListViewItem listviewX, listviewY;
// Cast the objects to be compared to ListViewItem objects
listviewX = (ListViewItem)x;
listviewY = (ListViewItem)y;
ListView listViewMain = listviewX.ListView;
// Calculate correct return value based on object comparison
if (listViewMain != null && (listViewMain.Sorting != SortOrder.Ascending && listViewMain.Sorting != SortOrder.Descending))
{
// Return '0' to indicate they are equal
return(compareResult);
}
if (sortModifier.Equals(SortModifiers.SortByText) || ColumnToSort > 0)
{
// Compare the two items
if (listviewX.SubItems.Count <= ColumnToSort && listviewY.SubItems.Count <= ColumnToSort)
{
compareResult = ObjectCompare.Compare(null, null);
}
else if (listviewX.SubItems.Count <= ColumnToSort && listviewY.SubItems.Count > ColumnToSort)
{
compareResult = ObjectCompare.Compare(null, listviewY.SubItems[ColumnToSort].Text.Trim());
}
else if (listviewX.SubItems.Count > ColumnToSort && listviewY.SubItems.Count <= ColumnToSort)
{
compareResult = ObjectCompare.Compare(listviewX.SubItems[ColumnToSort].Text.Trim(), null);
}
else
{
compareResult = ObjectCompare.Compare(listviewX.SubItems[ColumnToSort].Text.Trim(), listviewY.SubItems[ColumnToSort].Text.Trim());
}
}
else
{
switch (sortModifier)
{
case SortModifiers.SortByCheckbox:
compareResult = CheckBoxObjectCompare.Compare(x, y);
break;
case SortModifiers.SortByImage:
compareResult = TextObjectCompare.Compare(x, y);
break;
case SortModifiers.SortCustom:
compareResult = CustomCompare.Compare(x, y);
break;
default:
compareResult = TextObjectCompare.Compare(x, y);
break;
}
}
// Calculate correct return value based on object comparison
if (OrderOfSort == SortOrder.Ascending)
{
// Ascending sort is selected, return normal result of compare operation
return(compareResult);
}
else if (OrderOfSort == SortOrder.Descending)
{
// Descending sort is selected, return negative result of compare operation
return(-compareResult);
}
else
{
// Return '0' to indicate they are equal
return(0);
}
}