リストボックス内のアイテムを上下に移動する方法は？
ListBox1オブジェクトがあり、いくつかのアイテムが含まれています。選択したアイテムを上に移動するボタンと、選択したアイテムを下に移動するボタンがあります。 2つのボタンのコードはどうあるべきですか？
private void UpClick()
{
// only if the first item isn't the current one
if(listBox1.ListIndex > 0)
{
// add a duplicate item up in the listbox
listBox1.AddItem(listBox1.Text, listBox1.ListIndex - 1);
// make it the current item
listBox1.ListIndex = (listBox1.ListIndex - 2);
// delete the old occurrence of this item
listBox1.RemoveItem(listBox1.ListIndex + 2);
}
}
private void DownClick()
{
// only if the last item isn't the current one
if((listBox1.ListIndex != -1) && (listBox1.ListIndex < listBox1.ListCount - 1))
{
// add a duplicate item down in the listbox
listBox1.AddItem(listBox1.Text, listBox1.ListIndex + 2);
// make it the current item
listBox1.ListIndex = listBox1.ListIndex + 2;
// delete the old occurrence of this item
listBox1.RemoveItem(listBox1.ListIndex - 2);
}
}
public void MoveUp()
{
MoveItem(-1);
}
public void MoveDown()
{
MoveItem(1);
}
public void MoveItem(int direction)
{
// Checking selected item
if (listBox1.SelectedItem == null || listBox1.SelectedIndex < 0)
return; // No selected item - nothing to do
// Calculate new index using move direction
int newIndex = listBox1.SelectedIndex + direction;
// Checking bounds of the range
if (newIndex < 0 || newIndex >= listBox1.Items.Count)
return; // Index out of range - nothing to do
object selected = listBox1.SelectedItem;
// Removing removable element
listBox1.Items.Remove(selected);
// Insert it in new position
listBox1.Items.Insert(newIndex, selected);
// Restore selection
listBox1.SetSelected(newIndex, true);
}
グーグルで検索してみましたか？ リストボックスコントロールでアイテムを上下に移動する たとえば。
public class SmartListBox : ListBox
{
//Moves the selected items up one level
public MoveUp()
{
for(int i = 0; i < Items.Count; i++)
{
if (Items[i].Selected)//identify the selected item
{
//swap with the top item(move up)
if (i > 0 && !Items[i - 1].Selected)
{
ListItem bottom = Items[i];
Items.Remove(bottom);
Items.Insert(i - 1, bottom);
Items[i - 1].Selected = true;
}
}
}
}
//Moves the selected items one level down
public MoveDown()
{
int startindex = Items.Count -1;
for (int i = startindex; i > -1; i--)
{
if (Items[i].Selected)//identify the selected item
{
//swap with the lower item(move down)
if (i < startindex && !Items[i + 1].Selected)
{
ListItem bottom = Items[i];
Items.Remove(bottom);
Items.Insert(i + 1, bottom);
Items[i + 1].Selected = true;
}
}
}
}
}
DataSourceプロパティを使用してListBoxにデータバインドされたアイテムを移動できるように@Saveコードを変更しました。
public void MoveItem(int direction)
{
// Checking selected item
if (listBox1.SelectedItem == null || listBox1.SelectedIndex < 0)
return; // No selected item - nothing to do
// Calculate new index using move direction
int newIndex = listBox1.SelectedIndex + direction;
// Checking bounds of the range
if (newIndex < 0 || newIndex >= listBox1.Items.Count)
return; // Index out of range - nothing to do
UnifyCamera selected = listBox1.SelectedItem as UnifyCamera;
// modify the data source list
inputData.Cameras.RemoveAt(listBox1.SelectedIndex);
inputData.Cameras.Insert(newIndex, selected);
// re-bind your data source
((ListBox)listBox1).DataSource = null;
((ListBox)listBox1).DataSource = this.inputData.Cameras;
((ListBox)listBox1).DisplayMember = "Name";
// Restore selection
listBox1.SetSelected(newIndex, true);
}
ここで、UnifyCameraは、inputData.Camerasを返すリストList<UnifyCamera>に格納されているカスタムクラスです。
上記のDesolatorコードを変更して、コントロールをパラメーターとして渡す...再利用可能
private void MoveUp()
{
MoveItem(-1,listBox1);
}
private void MoveDown()
{
MoveItem(1,listBox1);
}
public void MoveItem(int direction,ListBox listBox)
{
// Checking selected item
if (listBox.SelectedItem == null || listBox.SelectedIndex < 0)
return; // No selected item - nothing to do
// Calculate new index using move direction
int newIndex = listBox.SelectedIndex + direction;
// Checking bounds of the range
if (newIndex < 0 || newIndex >= listBox.Items.Count)
return; // Index out of range - nothing to do
object selected = listBox.SelectedItem;
// Removing removable element
listBox.Items.Remove(selected);
// Insert it in new position
listBox.Items.Insert(newIndex, selected);
// Restore selection
listBox.SetSelected(newIndex, true);
}
Vexeの答えは私にとって最高の働きをしましたが、いくつかの問題を修正するために修正する必要がありました。このソリューションは、同じオブジェクトがリストボックスに複数回ある場合、正しいオブジェクトを強調表示します。また、このソリューションは、複数選択されたオブジェクトがリストボックスの上部または下部にヒットし、ボタンが何度も押され続けたときに、フリップフロップするのを防ぎます。
private void btnMoveUp_Click(object sender, EventArgs e)
{
// find the lowest index of non selected items
int lowestIndexNotSelected = listBox.Items.Count - 1;
for (int i = listBox.Items.Count - 1; i >= 0; i--)
{
if (!listBox.SelectedIndices.Contains(i))
{
lowestIndexNotSelected = i;
}
}
listBox.BeginUpdate();
int numberOfSelectedItems = listBox.SelectedItems.Count;
for (int i = 0; i < numberOfSelectedItems; i++)
{
// only if it's not a lower inde than the lowest non selected index
if (listBox.SelectedIndices[i] > lowestIndexNotSelected)
{
// the index of the item above the item that we wanna move up
int indexToInsertIn = listBox.SelectedIndices[i] - 1;
// insert UP the item that we want to move up
listBox.Items.Insert(indexToInsertIn, listBox.SelectedItems[i]);
// removing it from its old place
listBox.Items.RemoveAt(indexToInsertIn + 2);
// highlighting it in its new place (by index, to prevent highlighting wrong instance)
listBox.SelectedIndex = indexToInsertIn;
}
}
listBox.EndUpdate();
}
private void btnMoveDown_Click(object sender, EventArgs e)
{
// find the highest index of non selected items
int highestIndexNonSelected = 0;
for (int i = 0; i < listBox.Items.Count; i++)
{
if (!listBox.SelectedIndices.Contains(i))
{
highestIndexNonSelected = i;
}
}
listBox.BeginUpdate();
int numberOfSelectedItems = listBox.SelectedItems.Count;
// when going down, instead of moving through the selected items from top to bottom
// we'll go from bottom to top, it's easier to handle this way.
for (int i = numberOfSelectedItems - 1; i >= 0; i--)
{
// only if it's not a higher index than the highest index not selected
if (listBox.SelectedIndices[i] < highestIndexNonSelected)
{
// the index of the item that is currently below the selected item
int indexToInsertIn = listBox.SelectedIndices[i] + 2;
// insert DOWN the item that we want to move down
listBox.Items.Insert(indexToInsertIn, listBox.SelectedItems[i]);
// removing it from its old place
listBox.Items.RemoveAt(indexToInsertIn - 2);
// highlighting it in its new place (by index, to prevent highlighting wrong instance)
listBox.SelectedIndex = indexToInsertIn - 1;
}
}
listBox.EndUpdate();
}
他のすべての答えは問題ありませんが、これも考慮する必要があります:)その考えはSwDevMan81からのものに近いですが、これは実際のコード（擬似ではない）であり、複数のアイテム（複数の選択アイテム）を移動できます下に移動するときに改善されました。
private void MoveUp_listBox_button_Click(object sender, EventArgs e)
{
listBox.BeginUpdate();
int numberOfSelectedItems = listBox.SelectedItems.Count;
for (int i = 0; i < numberOfSelectedItems; i++)
{
// only if it's not the first item
if (listBox.SelectedIndices[i] > 0)
{
// the index of the item above the item that we wanna move up
int indexToInsertIn = listBox.SelectedIndices[i] - 1;
// insert UP the item that we want to move up
listBox.Items.Insert(indexToInsertIn, listBox.SelectedItems[i]);
// removing it from its old place
listBox.Items.RemoveAt(indexToInsertIn + 2);
// highlighting it in its new place
listBox.SelectedItem = listBox.Items[indexToInsertIn];
}
}
listBox.EndUpdate();
}
private void MoveDown_listBox_button_Click(object sender, EventArgs e)
{
listBox.BeginUpdate();
int numberOfSelectedItems = listBox.SelectedItems.Count;
// when going down, instead of moving through the selected items from top to bottom
// we'll go from bottom to top, it's easier to handle this way.
for (int i = numberOfSelectedItems-1; i >= 0; i--)
{
// only if it's not the last item
if (listBox.SelectedIndices[i] < listBox.Items.Count - 1)
{
// the index of the item that is currently below the selected item
int indexToInsertIn = listBox.SelectedIndices[i] + 2;
// insert DOWN the item that we want to move down
listBox.Items.Insert(indexToInsertIn, listBox.SelectedItems[i]);
// removing it from its old place
listBox.Items.RemoveAt(indexToInsertIn - 2);
// highlighting it in its new place
listBox.SelectedItem = listBox.Items[indexToInsertIn - 1];
}
}
listBox.EndUpdate();
}
public static void MoveUpOrDownSelectedItem(ListBox LisBox, bool MoveUp)
{
if (LisBox.SelectedIndex > 0 && MoveUp)
{
// add a duplicate item up in the listbox
LisBox.Items.Insert(LisBox.SelectedIndex - 1, LisBox.SelectedItem);
// make it the current item
LisBox.SelectedIndex = (LisBox.SelectedIndex - 2);
// delete the old occurrence of this item
LisBox.Items.RemoveAt(LisBox.SelectedIndex + 2);
}
if ((LisBox.SelectedIndex != -1) && (LisBox.SelectedIndex < LisBox.Items.Count- 1) && MoveUp == false)
{
// add a duplicate item down in the listbox
int IndexToRemove = LisBox.SelectedIndex;
LisBox.Items.Insert(LisBox.SelectedIndex + 2, LisBox.SelectedItem);
// make it the current item
LisBox.SelectedIndex = (LisBox.SelectedIndex + 2);
// delete the old occurrence of this item
LisBox.Items.RemoveAt(IndexToRemove);
}
}
// Options is a list box
private void MoveUpButton_Click(object sender,EventArgs e) {
int index = Options.SelectedIndex;
if (index <= 0) return;
string item = (string)Options.Items[index - 1];
Options.Items.RemoveAt(index - 1);
Options.Items.Insert(index,item);
selectedIndexChanged(null,null);
}
private void MoveDnButton_Click(object sender,EventArgs e) {
int index = Options.SelectedIndex;
if (index + 1 >= Options.Items.Count) return;
string item = (string)Options.Items[index];
Options.Items.RemoveAt(index);
Options.Items.Insert(index + 1,item);
Options.SelectedIndex = index + 1;
}
// sent when user makes a selection or when he moves an item up or down
private void selectedIndexChanged(object sender,EventArgs e) {
int index = Selected.SelectedIndex;
MoveUpButton.Enabled = index > 0;
MoveDnButton.Enabled = index + 1 < Selected.Items.Count;
}
private void btnUp_Click(object sender, System.EventArgs e)
{
if (this.lbItems.SelectedIndex == -1 || this.lbItems.SelectedIndex == 0)
return;
Object select, previous, temp;
select = lbItems.Items[lbItems.SelectedIndex];
previous = lbItems.Items[lbItems.SelectedIndex-1];
temp = select;
select = previous;
previous = temp;
lbItems.Items[lbItems.SelectedIndex] = select;
lbItems.Items[lbItems.SelectedIndex-1] = previous;
lbItems.SelectedIndex--;
}
private void btnDown_Click(object sender, System.EventArgs e)
{
if (this.lbItems.SelectedIndex == -1 || this.lbItems.SelectedIndex == lbItems.Items.Count-1)
return;
Object select, next, temp;
select = lbItems.Items[lbItems.SelectedIndex];
next = lbItems.Items[lbItems.SelectedIndex+1];
temp = select;
select = next;
next = temp;
lbItems.Items[lbItems.SelectedIndex] = select;
lbItems.Items[lbItems.SelectedIndex+1] = next;
lbItems.SelectedIndex++;
}
選択したアイテムのコレクションを取得し、次のように移動します。
private void btnMoveUp_Click(object sender, EventArgs e)
{
HashSet<KeyValuePair<int, object>> ItemsToMove = new HashSet<KeyValuePair<int, object>>();
foreach (object o in lstMyListView.SelectedItems)
ItemsToMove.Add(new KeyValuePair<int, object>(lstMyListView.Items.IndexOf(o), o));
foreach (KeyValuePair<int, object> kvp in ItemsToMove)
{
if (kvp.Key > 0) // check if its the first item before moving
{
lstMyListView.Items.Remove(kvp.Value);
lstMyListView.Items.Insert(kvp.Key - 1, kvp.Value);
}
}
}
private void btnMoveDown_Click(object sender, EventArgs e)
{
HashSet<KeyValuePair<int, object>> ItemsToMove = new HashSet<KeyValuePair<int, object>>();
foreach (object o in lstMyListView.SelectedItems)
ItemsToMove.Add(new KeyValuePair<int, object>(lstMyListView.Items.IndexOf(o), o));
foreach (KeyValuePair<int, object> kvp in ItemsToMove)
{
if (kvp.Key < lstMyListView.Items.Count - 1) // check if its the last item before moving
{
lstMyListView.Items.Remove(kvp.Value);
lstMyListView.Items.Insert(kvp.Key + 1, kvp.Value);
}
}
}
DataSourceにバインドできるListBoxを処理する一般的な方法を探している人のために、通常のバインドされたListBoxを処理する Save's answer に基づく一般的な拡張機能があります。
public static void MoveUp(this ListBox listBox)
{
listBox.MoveItem(-1);
}
public static void MoveDown(this ListBox listBox)
{
listBox.MoveItem(1);
}
public static void MoveItem(this ListBox listBox, int direction)
{
// Checking selected item
if (listBox.SelectedItem == null || listBox.SelectedIndex < 0)
return; // No selected item - nothing to do
// Calculate new index using move direction
int newIndex = listBox.SelectedIndex + direction;
// Checking bounds of the range
if (newIndex < 0 || newIndex >= listBox.Items.Count)
return; // Index out of range - nothing to do
//Find our if we're dealing with a BindingSource
bool isBindingSource = listBox.DataSource is BindingSource;
//Get the list
System.Collections.IList list = isBindingSource ? ((BindingSource)listBox.DataSource).List : listBox.Items;
object selected = listBox.SelectedItem;
// Removing removable element
list.Remove(selected);
// Insert it in new position
list.Insert(newIndex, selected);
// Restore selection
listBox.SetSelected(newIndex, true);
if (isBindingSource)
{
//Reset the binding if needed
((BindingSource)listBox.DataSource).ResetBindings(false);
}
}
これを複数の選択で使用します。また、インターリーブされた選択でも機能します。
private void Order_buttons_Click(object sender, EventArgs e)
{
//If noselection return
if (Layouts_listBox.SelectedItems.Count == 0) return;
//Determines wether up or down
int movement = (sender as Button) == Order_Upbutton? - 1 : 1;
//creates a dictionary associating the original Index (ListBox) to the text
Dictionary<int, string> Items = new Dictionary<int, string>();
//Also creates a list with the Index for sorting
List<int> DesiredOrder = new List<int>();
//Cycle through the selection and fill both the list and dictionary
ListBox.SelectedObjectCollection NN = Layouts_listBox.SelectedItems;
foreach (object n in NN)
{
DesiredOrder.Add(Layouts_listBox.Items.IndexOf(n));
Items.Add(Layouts_listBox.Items.IndexOf(n), (string)n);
}
//Sort the List according to the desired button (Up or Down)
DesiredOrder.Sort();
if ((sender as Button) != Order_Upbutton) DesiredOrder.Reverse();
//I'm using this ErrorHandling but thats up to you
try
{
//Call the MoveItem (Credits to Save) according to the sorted order
foreach (int n in DesiredOrder) MoveItem(movement, Items[n]);
}
catch (Exception)
{
SystemSounds.Asterisk.Play();
}
}
public void MoveItem(int direction, string Selected)
{
// Checking selected item
if (!Layouts_listBox.Items.Contains(Selected) || Layouts_listBox.Items.IndexOf(Selected) < 0)
throw new System.Exception(); // No selected item - Cancel entire Func
// Calculate new index using move direction
int newIndex = Layouts_listBox.Items.IndexOf(Selected) + direction;
// Checking bounds of the range
if (newIndex < 0 || newIndex >= Layouts_listBox.Items.Count)
throw new System.Exception(); // Index out of range - Cancel entire Func
object selected = Layouts_listBox.Items[Layouts_listBox.Items.IndexOf(Selected)];
// Removing removable element
Layouts_listBox.Items.Remove(selected);
// Insert it in new position
Layouts_listBox.Items.Insert(newIndex, selected);
// Restore selection
Layouts_listBox.SetSelected(newIndex, true);
}
上ボタンの場合：
private void UpBottom_Click(object sender, EventArgs e)
{
//this.Options is ListBox
if (this.Options.SelectedIndex == -1 ||
this.Options.SelectedIndex == 0)
return;
string item, aboveItem;
int itemIndex, aboveItemIndex;
itemIndex = this.Options.SelectedIndex;
aboveItemIndex = this.Options.SelectedIndex - 1;
item = (string)this.Options.Items[itemIndex];
aboveItem = (string)this.Options.Items[aboveItemIndex];
this.Options.Items.RemoveAt(aboveItemIndex);
this.Options.Items.Insert(itemIndex, aboveItem);
}
下ボタンの場合：
private void DownButton_Click(object sender, EventArgs e)
{
//this.Options is ListBox
if (this.Options.SelectedIndex == -1 ||
this.Options.SelectedIndex >= this.Options.Items.Count)
return;
string item, belowItem;
int itemIndex, belowItemIndex;
itemIndex = this.Options.SelectedIndex;
belowItemIndex = this.Options.SelectedIndex + 1;
if (belowItemIndex >= this.Options.Items.Count)
return;
item = (string)this.Options.Items[itemIndex];
belowItem = (string)this.Options.Items[belowItemIndex];
this.Options.Items.RemoveAt(itemIndex);
this.Options.Items.Insert(belowItemIndex, item);
this.Options.SelectedIndex = belowItemIndex;
}
選択したアイテムを移動するために、この関数を作成しました。
using System.Collections;
using System.Collections.Generic;
private void MoveListboxItems(int step, ListBox lb) {
/* 'step' should be:
* -1 for moving selected items up
* 1 for moving selected items down
* 'lb' is your ListBox
* see examples how to call below this function
*/
try {
// do only something when really an item is selected
if (lb.SelectedIndex > -1) {
// get some needed values - they change while we manipulate the listbox
// but we need them as they was original
IList SelectedItems = lb.SelectedItems;
IList SelectedIndices = lb.SelectedIndices;
// set some default values
int selIndex = -1;
int newIndex = -1;
int selCount = SelectedItems.Count;
int lc = 0;
int mc = 0;
string moveOldValue = string.Empty;
string selectedItemValue = string.Empty;
if (step == 1) {
mc = selCount - 1;
} else {
mc = lc;
}
// enter the loop through the selected items
while (lc < selCount) {
selectedItemValue = string.Empty;
moveOldValue = string.Empty;
try {
// get the item that should get moved
selectedItemValue = SelectedItems[mc].ToString();
selIndex = Convert.ToInt32(SelectedIndices[mc]);
} catch {
selIndex = -1;
}
// gen index for new place
newIndex = selIndex + step;
try {
// get the old value from the place where the item get moved
moveOldValue = lb.Items[newIndex].ToString();
} catch { /* do nothing */ }
try {
if (!String.IsNullOrEmpty(selectedItemValue) && !String.IsNullOrEmpty(moveOldValue) && selIndex != -1 && newIndex != -1 && !lb.SelectedIndices.Contains(newIndex)) {
// move selected item
lb.Items.RemoveAt(newIndex);
lb.Items.Insert(newIndex, selectedItemValue);
// write old value back to the old place from selected item
lb.Items.RemoveAt(selIndex);
lb.Items.Insert(selIndex, moveOldValue);
// hold the moved item selected
lb.SetSelected(newIndex, true);
}
} catch { /* do nothing */ }
lc++;
if (step == 1) {
mc -= step;
} else {
mc = lc;
}
}
}
} catch { /* do nothing */ };
}
// examples how i call the function above
void BtnLbUp_Click(object sender, EventArgs e) {
MoveListboxItems(-1, this.lbMyList);
}
void BtnLbDown_Click(object sender, EventArgs e) {
MoveListboxItems(1, this.lbMyList);
}