Select / Deselect Items in multiple listboxes based on selection of an item in one listbox

I have a scenario where I have three listboxes. Multiple Items can be selected in the listboxes. Based on the selection of items in one listbox, I need to select and deselect the corresponding rows in the other listboxes.

I have the code below, but I am missing something. When I select and deselecting the item, it selects and deselects the other rows items incorrectly.

            for (int count = 0; count < listBox_1.SelectedIndices.Count; count  )
            {
                // Determine if the item is selected.
                if (listBox_1.GetSelected(count) == true)
                {
                    listBox_2.SetSelected(listBox_1.SelectedIndices[count], false);
                    listBox_3.SetSelected(listBox_1.SelectedIndices[count], false);
                }
                else if (listBox_1.GetSelected(count) == false)
                {
                    // Select all items that are not selected.
                    listBox_2.SetSelected(listBox_1.SelectedIndices[count], true);
                    listBox_3.SetSelected(listBox_1.SelectedIndices[count], true);
                }

            }

Here Selection of items in LB1 should control the selection in LB2 and LB3. Now, since Item 2 and 3 are selected in LB1 - items 2 and 3 should be selected in LB2 and LB3 as well. But that's not what's happening.

CodePudding user response：

Here Selection of items in LB1 should control the selection in LB2 and LB3. Now, since Item 2 and 3 are selected in LB1 - items 2 and 3 should be selected in LB2 and LB3 as well. But that's not what's happening.

I would recommend looping through all items of listBox_1...

for (int idx = 0; idx <= listBox_1.Items.Count - 1; idx  )
            {
                if (listBox_1.GetSelected(idx))
                {
                    if (idx <= listBox_2.Items.Count)
                        listBox_2.SetSelected(idx, true);
                    if (idx <= listBox_3.Items.Count)
                        listBox_3.SetSelected(idx, true);
                }
                else
                {
                    if (idx <= listBox_2.Items.Count)
                        listBox_2.SetSelected(idx, false);
                    if (idx <= listBox_3.Items.Count)
                        listBox_3.SetSelected(idx, false);
                }
            }

Please note, I put a check as well to make sure the index would exist, otherwise it could throw an error if the index doesn't exist.

CodePudding user response：

It is unclear where this code is called. I would simply clear the other list2 and list3 boxes and then set the same selected indexes as the ones in list box 1... some thing like...

  listBox_2.ClearSelected();
  listBox_3.ClearSelected();
  foreach (int selectedItem in listBox_1.SelectedIndices) {
    listBox_2.SetSelected(selectedItem, true);
    listBox_3.SetSelected(selectedItem, true);
  }