I'm trying
to understand what's happening here. I have a CheckedListBox which contains some ticked and some un-ticked items. I'm trying
to find a way of determining the delta in the selection of controls. I've tried some cumbersome like this - but only works part of the time, I'm sure there's a more elegant solution. A maybe related problem is the myCheckBox_ItemCheck event fires on form load - before I have a chance
to perform an ItemCheck. Here's what I have so far:
void clbProgs_ItemCheck(object sender, ItemCheckEventArgs e)
{
// i know its awful
System.Windows.Forms.CheckedListBox cb = (System.Windows.Forms.CheckedListBox)sender;
string sCurrent = e.CurrentValue.ToString();
int sIndex = e.Index;
AbstractLink lk = (AbstractLink)cb.Items[sIndex];
List<ILink> _links = clbProgs.DataSource as List<ILink>;
foreach (AbstractLink lkCurrent in _links)
{
if (!lkCurrent.IsActive)
{
if (!_groupValues.ContainsKey(lkCurrent.Linkid))
{
_groupValues.Add(lkCurrent.Linkid, lkCurrent);
}
}
}
if (_groupValues.ContainsKey(lk.Linkid))
{
AbstractLink lkDirty = (AbstractLink)lk.Clone();
CheckState newValue = (CheckState)e.NewValue;
if (newValue == CheckState.Checked)
{
lkDirty.IsActive = true;
}
else if (newValue == CheckState.Unchecked)
{
lkDirty.IsActive = false;
}
if (_dirtyGroups.ContainsKey(lk.Linkid))
{
_dirtyGroups[lk.Linkid] = lkDirty;
}
else
{
CheckState oldValue = (CheckState)e.NewValue;
if (oldValue == CheckState.Checked)
{
lkDirty.IsActive = true;
}
else if (oldValue == CheckState.Unchecked)
{
lkDirty.IsActive = false;
}
_dirtyGroups.Add(lk.Linkid, lk);
}
}
else
{
if (!lk.IsActive)
{
_dirtyGroups.Add(lk.Linkid, lk);
}
else
{
_groupValues.Add(lk.Linkid, lk);
}
}
}
Then onclick of a save button - I check whats changed before sending
to database:
private void btSave_Click(object sender, EventArgs e)
{
List<AbstractLink> originalList = new List<AbstractLink>(_groupValues.Values);
List<AbstractLink> changedList = new List<AbstractLink>(_dirtyGroups.Values);
IEnumerable<AbstractLink> dupes = originalList.ToArray<AbstractLink>().Intersect(changedList.ToArray<AbstractLink>());
foreach (ILink t in dupes)
{
MessageBox.Show("Changed");
}
if (dupes.Count() == 0)
{
MessageBox.Show("No Change");
}
}
For further info. The definition of type AbstractLink uses:
public bool Equals(ILink other)
{
if (Object.ReferenceEquals(other, null)) return false;
if (Object.ReferenceEquals(this, other)) return true;
return IsActive.Equals(other.IsActive) && Linkid.Equals(other.Linkid);
}
