ListView.Clear メソッド

.NET Framework クラス ライブラリ リファレンス

ListView.Clear メソッド

コントロールからすべての項目と列を削除します。

名前空間: System.Windows.Forms
アセンブリ: System.Windows.Forms (system.windows.forms.dll 内)
構文

Visual Basic (宣言)

Public Sub Clear

Visual Basic (使用法)

Dim instance As ListView

instance.Clear

C#

public void Clear ()

C++

public:
void Clear ()

J#

public void Clear ()

JScript

public function Clear ()

解説

このメソッドを使用すると、ListView.ColumnHeaderCollection クラスおよび ListView.ListViewItemCollection クラスから個別の Clear メソッドを呼び出すことなく、ListView コントロールからすべての項目と列を削除できます。

メモ
Clear メソッドは、ListView コントロールに指定された Groups を削除しません。Groups を削除するには、ListViewGroupCollection.Clear を呼び出してください。

使用例

Clear メンバおよび ListViewItem.Selected メンバの使用方法のコード例を次に示します。この例を実行するには、ListView1 という名前の ListView と、フォームの下の方に Button1 という名前のボタンが配置されているフォームに次のコードを貼り付けます。そして、フォームのコンストラクタまたはLoad メソッドから InitializeListView メソッドを呼び出します。

Visual Basic

Private Sub InitializeListView()

    ' Set up the inital values for the ListView and populate it.
    Me.ListView1 = New ListView
    Me.ListView1.Dock = DockStyle.Top
    Me.ListView1.Location = New System.Drawing.Point(0,
 0)
    Me.ListView1.Size = New System.Drawing.Size(292,
 130)
    Me.ListView1.View = View.Details
    Me.ListView1.FullRowSelect = True

    Dim breakfast() As String
 = New String() {"Continental
 Breakfast", "Pancakes and Sausage", _
   "Denver Omelet", "Eggs &
 Bacon", "Bagel & Cream Cheese"}

    Dim breakfastPrices() As String
 = New String() {"3.09",
 "4.09", "4.19", _
       "4.79", "2.09"}

    PopulateMenu("Breakfast", breakfast, breakfastPrices)
End Sub

Private Sub PopulateMenu(ByVal
 meal As String, _
    ByVal menuItems() As String,
 ByVal menuPrices() As String)
    Dim columnHeader1 As New
 ColumnHeader
    With columnHeader1
        .Text = meal & " Choices"
        .TextAlign = HorizontalAlignment.Left
        .Width = 146
    End With
    Dim columnHeader2 As New
 ColumnHeader
    With columnHeader2
        .Text = "Price"
        .TextAlign = HorizontalAlignment.Center
        .Width = 142
    End With
    Me.ListView1.Columns.Add(columnHeader1)
    Me.ListView1.Columns.Add(columnHeader2)

    Dim count As Integer

    For count = 0 To menuItems.Length - 1
        Dim listItem As New
 ListViewItem(menuItems(count))
        listItem.SubItems.Add(menuPrices(count))
        ListView1.Items.Add(listItem)
    Next

    ' Use the Selected property to select the first item on 
    ' the list.
    ListView1.Focus()
    ListView1.Items(0).Selected = True
End Sub


Private Sub Button1_Click(ByVal
 sender As System.Object, _
    ByVal e As System.EventArgs) Handles
 Button1.Click

    ' Create new values for the ListView, clear the list, 
    ' and repopulate it.
    Dim lunch() As String
 = New String() {"Hamburger",
 _ 
        "Grilled Cheese", "Soup
 & Salad", "Club Sandwich", "Hotdog"}

    Dim lunchPrices() As String
 = New String() {"4.09",
 "5.09", _
        "5.19", "4.79",
 "2.09"}

    ListView1.Clear()

    PopulateMenu("Lunch", lunch, lunchPrices)
    Button1.Enabled = False
End Sub

C#

private void InitializeListView()
{
    // Set up the inital values for the ListView and populate it.
    this.ListView1 = new ListView();
    this.ListView1.Dock = DockStyle.Top;
    this.ListView1.Location = new System.Drawing.Point(0,
 0);
    this.ListView1.Size = new System.Drawing.Size(292,
 130);
    this.ListView1.View = View.Details;
    this.ListView1.FullRowSelect = true;

    string[] breakfast = new string[]{"Continental
 Breakfast", 
        "Pancakes and Sausage", "Denver Omelet", "Eggs &
 Bacon", 
        "Bagel & Cream Cheese"};

    string[] breakfastPrices = new string[]{"3.09",
 "4.09", 
        "4.19", "4.79", "2.09"};

    PopulateMenu("Breakfast", breakfast, breakfastPrices);
}

private void PopulateMenu(string
 meal, 
    string[] menuItems, string[] menuPrices)
{
    ColumnHeader columnHeader1 = new ColumnHeader();
    columnHeader1.Text = meal + " Choices";
    columnHeader1.TextAlign = HorizontalAlignment.Left;
    columnHeader1.Width = 146;

    ColumnHeader columnHeader2 = new ColumnHeader();
    columnHeader2.Text = "Price";
    columnHeader2.TextAlign = HorizontalAlignment.Center;
    columnHeader2.Width = 142;

    this.ListView1.Columns.Add(columnHeader1);
    this.ListView1.Columns.Add(columnHeader2);

    for(int count=0; count < menuItems.Length;
 count++)
    {
        ListViewItem listItem = 
            new ListViewItem(menuItems[count]);
        listItem.SubItems.Add(menuPrices[count]);
        ListView1.Items.Add(listItem);
    }

    // Use the Selected property to select the first item on 
    // the list.
    ListView1.Focus();
    ListView1.Items[0].Selected = true;
}


private void Button1_Click(System.Object sender,
 System.EventArgs e)
{
    // Create new values for the ListView, clear the list, 
    // and repopulate it.
    string[] lunch = new string[]{"Hamburger",
 "Grilled Cheese",
        "Soup & Salad", "Club Sandwich", "Hotdog"};

    string[] lunchPrices = new string[]{"4.09",
 "5.09", "5.19", 
        "4.79", "2.09"};

    ListView1.Clear();

    PopulateMenu("Lunch", lunch, lunchPrices);
    Button1.Enabled = false;
}

C++

private:
   void InitializeListView()
   {
      // Set up the inital values for the ListView and populate it.
      this->ListView1 = gcnew ListView;
      this->ListView1->Dock = DockStyle::Top;
      this->ListView1->Location = System::Drawing::Point(
 0, 0 );
      this->ListView1->Size = System::Drawing::Size( 292,
 130 );
      this->ListView1->View = View::Details;
      this->ListView1->FullRowSelect = true;
      array<String^>^breakfast = {"Continental Breakfast","Pancakes
 and Sausage","Denver Omelet","Eggs & Bacon","Bagel
 & Cream Cheese"};
      array<String^>^breakfastPrices = {"3.09","4.09","4.19"
,"4.79","2.09"};
      PopulateMenu( "Breakfast", breakfast, breakfastPrices );
   }

   void PopulateMenu( String^ meal, array<String^>^menuItems,
 array<String^>^menuPrices )
   {
      ColumnHeader^ columnHeader1 = gcnew ColumnHeader;
      columnHeader1->Text = String::Concat( meal, " Choices" );
      columnHeader1->TextAlign = HorizontalAlignment::Left;
      columnHeader1->Width = 146;
      ColumnHeader^ columnHeader2 = gcnew ColumnHeader;
      columnHeader2->Text = "Price";
      columnHeader2->TextAlign = HorizontalAlignment::Center;
      columnHeader2->Width = 142;
      this->ListView1->Columns->Add( columnHeader1 );
      this->ListView1->Columns->Add( columnHeader2 );
      for ( int count = 0; count < menuItems->Length;
 count++ )
      {
         ListViewItem^ listItem = gcnew ListViewItem( menuItems[ count ] );
         listItem->SubItems->Add( menuPrices[ count ] );
         ListView1->Items->Add( listItem );

      }
      
      // Use the Selected property to select the first item on 
      // the list.
      ListView1->Focus();
      ListView1->Items[ 0 ]->Selected = true;
   }

   void Button1_Click( System::Object^ /*sender*/, System::EventArgs^
 /*e*/ )
   {
      // Create new values for the ListView, clear the list, 
      // and repopulate it.
      array<String^>^lunch = {"Hamburger","Grilled Cheese","Soup
 & Salad","Club Sandwich","Hotdog"};
      array<String^>^lunchPrices = {"4.09","5.09","5.19"
,"4.79","2.09"};
      ListView1->Clear();
      PopulateMenu( "Lunch", lunch, lunchPrices );
      Button1->Enabled = false;
   }

J#

private void InitializeListView()
{
    // Set up the inital values for the ListView and populate it.
    this.listView1 = new ListView();
    this.listView1.set_Dock(DockStyle.Top);
    this.listView1.set_Location(new System.Drawing.Point(0,
 0));
    this.listView1.set_Size(new System.Drawing.Size(292,
 130));
    this.listView1.set_View(View.Details);
    this.listView1.set_FullRowSelect(true);

    String breakfast[] = new String[] { "Continental Breakfast"
,
        "Pancakes and Sausage", "Denver Omelet", "Eggs &
 Bacon",
        "Bagel & Cream Cheese" };

    String breakfastPrices[] = new String[] { "3.09",
 "4.09", "4.19",
        "4.79", "2.09" };

    PopulateMenu("Breakfast", breakfast, breakfastPrices);
} //InitializeListView

private void PopulateMenu(String meal,String
 menuItems[],String menuPrices[])
{
    ColumnHeader columnHeader1 = new ColumnHeader();
    columnHeader1.set_Text(meal + " Choices");
    columnHeader1.set_TextAlign(HorizontalAlignment.Left);
    columnHeader1.set_Width(146);

    ColumnHeader columnHeader2 = new ColumnHeader();
    columnHeader2.set_Text("Price");
    columnHeader2.set_TextAlign(HorizontalAlignment.Center);
    columnHeader2.set_Width(142);

    this.listView1.get_Columns().Add(columnHeader1);
    this.listView1.get_Columns().Add(columnHeader2);

    for (int count = 0; count < menuItems.length;
 count++) {
        ListViewItem listItem =
            new ListViewItem((String)menuItems.get_Item(count));
        listItem.get_SubItems().Add((String)menuPrices.get_Item(count));
        listView1.get_Items().Add(listItem);
    }
    // Use the Selected property to select the first item on 
    // the list.
    listView1.Focus();
    listView1.get_Items().get_Item(0).set_Selected(true);
} //PopulateMenu

private void button1_Click(System.Object sender,
 System.EventArgs e)
{
    // Create new values for the ListView, clear the list, 
    // and repopulate it.
    String lunch[] = new String[] { "Hamburger", "Grilled
 Cheese",
        "Soup & Salad", "Club Sandwich", "Hotdog"
 };

    String lunchPrices[] = new String[] { "4.09", "5.09",
 "5.19",
        "4.79", "2.09" };

    listView1.Clear();

    PopulateMenu("Lunch", lunch, lunchPrices);
    button1.set_Enabled(false);
} //button1_Click

プラットフォーム

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。

バージョン情報

.NET Framework
サポート対象 : 2.0、1.1、1.0
.NET Compact Framework
サポート対象 : 2.0、1.0

参照

関連項目
ListView クラス
ListView メンバ
System.Windows.Forms 名前空間
ListView.ColumnHeaderCollection.Clear
ListView.ListViewItemCollection.Clear