comboboxとは？ わかりやすく解説

<ClassInterfaceAttribute(ClassInterfaceType.AutoDispatch)> _
<ComVisibleAttribute(True)> _
Public Class ComboBox
    Inherits ListControl

Dim instance As ComboBox

[ClassInterfaceAttribute(ClassInterfaceType.AutoDispatch)] 
[ComVisibleAttribute(true)] 
public class ComboBox : ListControl

[ClassInterfaceAttribute(ClassInterfaceType::AutoDispatch)] 
[ComVisibleAttribute(true)] 
public ref class ComboBox : public
 ListControl

/** @attribute ClassInterfaceAttribute(ClassInterfaceType.AutoDispatch) */ 
/** @attribute ComVisibleAttribute(true) */ 
public class ComboBox extends ListControl

ClassInterfaceAttribute(ClassInterfaceType.AutoDispatch) 
ComVisibleAttribute(true) 
public class ComboBox extends
 ListControl

Imports System
Imports System.Windows.Forms

Namespace ComboBoxSampleNamespace

    Public Class ComboBoxSample
        Inherits System.Windows.Forms.Form

        Private addButton As System.Windows.Forms.Button
        Private textBox2 As System.Windows.Forms.TextBox
        Private addGrandButton As System.Windows.Forms.Button
        Private comboBox1 As System.Windows.Forms.ComboBox
        Private showSelectedButton As System.Windows.Forms.Button
        Private textBox1 As System.Windows.Forms.TextBox
        Private findButton As System.Windows.Forms.Button
        Private label1 As System.Windows.Forms.Label

        Public Sub New()
            MyBase.New()
            Me.InitializeComponent()
        End Sub

        <System.STAThreadAttribute()> Public Shared
 Sub Main()
            System.Windows.Forms.Application.Run(New ComboBoxSample())
        End Sub

        Private Sub InitializeComponent()
            Me.addButton = New System.Windows.Forms.Button()
            Me.textBox2 = New System.Windows.Forms.TextBox()
            Me.addGrandButton = New System.Windows.Forms.Button()
            Me.comboBox1 = New System.Windows.Forms.ComboBox()
            Me.showSelectedButton = New System.Windows.Forms.Button()
            Me.textBox1 = New System.Windows.Forms.TextBox()
            Me.findButton = New System.Windows.Forms.Button()
            Me.label1 = New System.Windows.Forms.Label()
            Me.addButton.Location = New System.Drawing.Point(248,
 32)
            Me.addButton.Size = New System.Drawing.Size(40,
 24)
            Me.addButton.TabIndex = 1
            Me.addButton.Text = "Add"
            AddHandler Me.addButton.Click,
 AddressOf Me.addButton_Click
            Me.textBox2.Location = New System.Drawing.Point(8,
 64)
            Me.textBox2.Size = New System.Drawing.Size(232,
 20)
            Me.textBox2.TabIndex = 6
            Me.textBox2.Text = ""
            Me.addGrandButton.Location = New
 System.Drawing.Point(8, 96)
            Me.addGrandButton.Size = New System.Drawing.Size(280,
 23)
            Me.addGrandButton.TabIndex = 2
            Me.addGrandButton.Text = "Add 1,000
 Items"
            AddHandler Me.addGrandButton.Click,
 AddressOf Me.addGrandButton_Click
            Me.comboBox1.Anchor = ((System.Windows.Forms.AnchorStyles.Bottom
 Or System.Windows.Forms.AnchorStyles.Left) _
                        Or System.Windows.Forms.AnchorStyles.Right)
            Me.comboBox1.DropDownWidth = 280
            Me.comboBox1.Items.AddRange(New
 Object() {"Item 1", "Item
 2", "Item 3", "Item 4", "Item 5"})
            Me.comboBox1.Location = New System.Drawing.Point(8,
 248)
            Me.comboBox1.Size = New System.Drawing.Size(280,
 21)
            Me.comboBox1.TabIndex = 7
            Me.showSelectedButton.Location = New
 System.Drawing.Point(8, 128)
            Me.showSelectedButton.Size = New
 System.Drawing.Size(280, 24)
            Me.showSelectedButton.TabIndex = 4
            Me.showSelectedButton.Text = "What
 Item is Selected?"
            AddHandler Me.showSelectedButton.Click,
 AddressOf Me.showSelectedButton_Click
            Me.textBox1.Location = New System.Drawing.Point(8,
 32)
            Me.textBox1.Size = New System.Drawing.Size(232,
 20)
            Me.textBox1.TabIndex = 5
            Me.textBox1.Text = ""
            Me.findButton.Location = New System.Drawing.Point(248,
 64)
            Me.findButton.Size = New System.Drawing.Size(40,
 24)
            Me.findButton.TabIndex = 3
            Me.findButton.Text = "Find"
            AddHandler Me.findButton.Click,
 AddressOf Me.findButton_Click
            Me.label1.Location = New System.Drawing.Point(8,
 224)
            Me.label1.Size = New System.Drawing.Size(144,
 23)
            Me.label1.TabIndex = 0
            Me.label1.Text = "Test ComboBox"
            Me.ClientSize = New System.Drawing.Size(292,
 273)
            Me.Controls.AddRange(New System.Windows.Forms.Control()
 {Me.comboBox1, Me.textBox2, Me.textBox1,
 Me.showSelectedButton, Me.findButton, Me.addGrandButton, Me.addButton, Me.label1})
            Me.Text = "ComboBox Sample"
        End Sub

        Private Sub addButton_Click(ByVal
 sender As Object, ByVal
 e As System.EventArgs)
            comboBox1.Items.Add(textBox1.Text)
        End Sub

        Private Sub findButton_Click(ByVal
 sender As Object, ByVal
 e As System.EventArgs)
            Dim index As Integer
            index = comboBox1.FindString(textBox2.Text)
            comboBox1.SelectedIndex = index
        End Sub

        Private Sub addGrandButton_Click(ByVal
 sender As Object, ByVal
 e As System.EventArgs)
            comboBox1.BeginUpdate()
            Dim I As Integer
            For I = 0 To 1000
                comboBox1.Items.Add("Item 1" + i.ToString())
            Next
            comboBox1.EndUpdate()
        End Sub

        Private Sub showSelectedButton_Click(ByVal
 sender As Object, ByVal
 e As System.EventArgs)
            Dim selectedIndex As Integer
            selectedIndex = comboBox1.SelectedIndex
            Dim selectedItem As Object
            selectedItem = comboBox1.SelectedItem

            MessageBox.Show("Selected Item Text: "
 & selectedItem.ToString() & Microsoft.VisualBasic.Constants.vbCrLf &
 _
                                "Index: " & selectedIndex.ToString())
        End Sub
    End Class
End Namespace

using System;
using System.Windows.Forms;

namespace Win32Form1Namespace {
    
    
    public class Win32Form1 : System.Windows.Forms.Form
 {
        private System.Windows.Forms.Button addButton;
        private System.Windows.Forms.TextBox textBox2;
        private System.Windows.Forms.Button addGrandButton;
        private System.Windows.Forms.ComboBox comboBox1;
        private System.Windows.Forms.Button showSelectedButton;
        private System.Windows.Forms.TextBox textBox1;
        private System.Windows.Forms.Button findButton;
        private System.Windows.Forms.Label label1;
        
        public Win32Form1() {
            this.InitializeComponent();
        }
        
        [System.STAThreadAttribute()]
        public static void
 Main() {
            System.Windows.Forms.Application.Run(new Win32Form1());
        }
        
        private void InitializeComponent()
 {
            this.addButton = new System.Windows.Forms.Button();
            this.textBox2 = new System.Windows.Forms.TextBox();
            this.addGrandButton = new System.Windows.Forms.Button();
            this.comboBox1 = new System.Windows.Forms.ComboBox();
            this.showSelectedButton = new System.Windows.Forms.Button();
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.findButton = new System.Windows.Forms.Button();
            this.label1 = new System.Windows.Forms.Label();
            this.addButton.Location = new System.Drawing.Point(248,
 32);
            this.addButton.Size = new System.Drawing.Size(40,
 24);
            this.addButton.TabIndex = 1;
            this.addButton.Text = "Add";
            this.addButton.Click += new System.EventHandler(this.addButton_Click);
            this.textBox2.Location = new System.Drawing.Point(8,
 64);
            this.textBox2.Size = new System.Drawing.Size(232,
 20);
            this.textBox2.TabIndex = 6;
            this.textBox2.Text = "";
            this.addGrandButton.Location = new
 System.Drawing.Point(8, 96);
            this.addGrandButton.Size = new
 System.Drawing.Size(280, 23);
            this.addGrandButton.TabIndex = 2;
            this.addGrandButton.Text = "Add 1,000 Items";
            this.addGrandButton.Click += new
 System.EventHandler(this.addGrandButton_Click);
            this.comboBox1.Anchor = ((System.Windows.Forms.AnchorStyles.Bottom
 | System.Windows.Forms.AnchorStyles.Left) 
                        | System.Windows.Forms.AnchorStyles.Right);
            this.comboBox1.DropDownWidth = 280;
            this.comboBox1.Items.AddRange(new
 object[] {"Item 1",
                        "Item 2",
                        "Item 3",
                        "Item 4",
                        "Item 5"});
            this.comboBox1.Location = new System.Drawing.Point(8,
 248);
            this.comboBox1.Size = new System.Drawing.Size(280,
 21);
            this.comboBox1.TabIndex = 7;
            this.showSelectedButton.Location = new
 System.Drawing.Point(8, 128);
            this.showSelectedButton.Size = new
 System.Drawing.Size(280, 24);
            this.showSelectedButton.TabIndex = 4;
            this.showSelectedButton.Text = "What Item is
 Selected?";
            this.showSelectedButton.Click += new
 System.EventHandler(this.showSelectedButton_Click);
            this.textBox1.Location = new System.Drawing.Point(8,
 32);
            this.textBox1.Size = new System.Drawing.Size(232,
 20);
            this.textBox1.TabIndex = 5;
            this.textBox1.Text = "";
            this.findButton.Location = new
 System.Drawing.Point(248, 64);
            this.findButton.Size = new System.Drawing.Size(40,
 24);
            this.findButton.TabIndex = 3;
            this.findButton.Text = "Find";
            this.findButton.Click += new System.EventHandler(this.findButton_Click);
            this.label1.Location = new System.Drawing.Point(8,
 224);
            this.label1.Size = new System.Drawing.Size(144,
 23);
            this.label1.TabIndex = 0;
            this.label1.Text = "Test ComboBox";
            this.ClientSize = new System.Drawing.Size(292,
 273);
            this.Controls.AddRange(new System.Windows.Forms.Control[]
 {this.comboBox1,
                        this.textBox2,
                        this.textBox1,
                        this.showSelectedButton,
                        this.findButton,
                        this.addGrandButton,
                        this.addButton,
                        this.label1});
            this.Text = "ComboBox Sample";
        }
        
        private void addButton_Click(object
 sender, System.EventArgs e) {
           comboBox1.Items.Add(textBox1.Text);
        }

        private void addGrandButton_Click(object
 sender, System.EventArgs e) {
            comboBox1.BeginUpdate();
            for (int i = 0; i < 1000; i++)
 {
                comboBox1.Items.Add("Item 1" + i.ToString());
            }
            comboBox1.EndUpdate();
        }

        private void findButton_Click(object
 sender, System.EventArgs e) {
            int index = comboBox1.FindString(textBox2.Text);
            comboBox1.SelectedIndex = index;
        }

        private void showSelectedButton_Click(object
 sender, System.EventArgs e) {
            int selectedIndex = comboBox1.SelectedIndex;
            Object selectedItem = comboBox1.SelectedItem;

            MessageBox.Show("Selected Item Text: " + selectedItem.ToString()
 + "\n" +
                            "Index: " + selectedIndex.ToString());
        }
    }
}

#using <System.dll>
#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>

using namespace System;
using namespace System::Windows::Forms;

namespace Win32Form1Namespace
{
   public ref class Win32Form1: public
 System::Windows::Forms::Form
   {
   private:
      System::Windows::Forms::Button^ addButton;
      System::Windows::Forms::TextBox^ textBox2;
      System::Windows::Forms::Button^ addGrandButton;
      System::Windows::Forms::ComboBox^ comboBox1;
      System::Windows::Forms::Button^ showSelectedButton;
      System::Windows::Forms::TextBox^ textBox1;
      System::Windows::Forms::Button^ findButton;
      System::Windows::Forms::Label ^ label1;

   public:
      Win32Form1()
      {
         this->InitializeComponent();
      }

   private:
      void InitializeComponent()
      {
         this->addButton = gcnew System::Windows::Forms::Button;
         this->textBox2 = gcnew System::Windows::Forms::TextBox;
         this->addGrandButton = gcnew System::Windows::Forms::Button;
         this->comboBox1 = gcnew System::Windows::Forms::ComboBox;
         this->showSelectedButton = gcnew System::Windows::Forms::Button;
         this->textBox1 = gcnew System::Windows::Forms::TextBox;
         this->findButton = gcnew System::Windows::Forms::Button;
         this->label1 = gcnew System::Windows::Forms::Label;
         this->addButton->Location = System::Drawing::Point(
 248, 32 );
         this->addButton->Size = System::Drawing::Size(
 40, 24 );
         this->addButton->TabIndex = 1;
         this->addButton->Text = "Add";
         this->addButton->Click += gcnew System::EventHandler(
            this, &Win32Form1::addButton_Click );
         this->textBox2->Location = System::Drawing::Point(
 8, 64 );
         this->textBox2->Size = System::Drawing::Size( 232,
 20 );
         this->textBox2->TabIndex = 6;
         this->textBox2->Text = "";
         this->addGrandButton->Location = System::Drawing::Point(
 8, 96 );
         this->addGrandButton->Size = System::Drawing::Size(
 280, 23 );
         this->addGrandButton->TabIndex = 2;
         this->addGrandButton->Text = "Add 1, 000 Items";
         this->addGrandButton->Click += gcnew System::EventHandler(
            this, &Win32Form1::addGrandButton_Click );
         this->comboBox1->Anchor = (System::Windows::Forms::AnchorStyles)(
            (System::Windows::Forms::AnchorStyles::Bottom | System::Windows::Forms::AnchorStyles::Left)
 |
             System::Windows::Forms::AnchorStyles::Right);
         this->comboBox1->DropDownWidth = 280;
         array<Object^>^ objectArray = {"Item 1",
            "Item 2",
            "Item 3",
            "Item 4",
            "Item 5"};
         this->comboBox1->Items->AddRange( objectArray
 );
         this->comboBox1->Location = System::Drawing::Point(
 8, 248 );
         this->comboBox1->Size = System::Drawing::Size(
 280, 21 );
         this->comboBox1->TabIndex = 7;
         this->showSelectedButton->Location = System::Drawing::Point(
 8, 128 );
         this->showSelectedButton->Size = System::Drawing::Size(
 280, 24 );
         this->showSelectedButton->TabIndex = 4;
         this->showSelectedButton->Text = "What Item
 is Selected?";
         this->showSelectedButton->Click += gcnew System::EventHandler(
 
            this, &Win32Form1::showSelectedButton_Click );
         this->textBox1->Location = System::Drawing::Point(
 8, 32 );
         this->textBox1->Size = System::Drawing::Size( 232,
 20 );
         this->textBox1->TabIndex = 5;
         this->textBox1->Text = "";
         this->findButton->Location = System::Drawing::Point(
 248, 64 );
         this->findButton->Size = System::Drawing::Size(
 40, 24 );
         this->findButton->TabIndex = 3;
         this->findButton->Text = "Find";
         this->findButton->Click += gcnew System::EventHandler(
 
            this, &Win32Form1::findButton_Click );
         this->label1->Location = System::Drawing::Point(
 8, 224 );
         this->label1->Size = System::Drawing::Size( 144,
 23 );
         this->label1->TabIndex = 0;
         this->label1->Text = "Test ComboBox";
         this->ClientSize = System::Drawing::Size( 292, 273
 );
         array<System::Windows::Forms::Control^>^ controlsArray = {this->comboBox1
,
            this->textBox2,
            this->textBox1,
            this->showSelectedButton,
            this->findButton,
            this->addGrandButton,
            this->addButton,
            this->label1};
         this->Controls->AddRange( controlsArray );
         this->Text = "ComboBox Sample";
      }

      void addButton_Click( Object^ sender, System::EventArgs^
 e )
      {
         comboBox1->Items->Add( textBox1->Text );
      }

      void addGrandButton_Click( Object^ sender, System::EventArgs^
 e )
      {
         comboBox1->BeginUpdate();
         for ( int i = 0; i < 1000; i++
 )
         {
            comboBox1->Items->Add( "Item 1 " + i.ToString() );

         }
         comboBox1->EndUpdate();
      }

      void findButton_Click( Object^ sender, System::EventArgs^
 e )
      {
         int index = comboBox1->FindString( textBox2->Text
 );
         comboBox1->SelectedIndex = index;
      }

      void showSelectedButton_Click( Object^ sender, System::EventArgs^
 e )
      {
         int selectedIndex = comboBox1->SelectedIndex;
         Object^ selectedItem = comboBox1->SelectedItem;
         MessageBox::Show( "Selected Item Text: " + selectedItem->ToString()
 + "\n" +
            "Index: " + selectedIndex.ToString() );
      }
   };
}


[System::STAThreadAttribute]
int main()
{
   System::Windows::Forms::Application::Run( gcnew Win32Form1Namespace::Win32Form1
 );
}

package Win32Form1Namespace;

import System.*;
import System.Windows.Forms.*;

public class Win32Form1 extends System.Windows.Forms.Form
{
    private System.Windows.Forms.Button addButton;
    private System.Windows.Forms.TextBox textBox2;
    private System.Windows.Forms.Button addGrandButton;
    private System.Windows.Forms.ComboBox comboBox1;
    private System.Windows.Forms.Button showSelectedButton;
    private System.Windows.Forms.TextBox textBox1;
    private System.Windows.Forms.Button findButton;
    private System.Windows.Forms.Label label1;

    public Win32Form1()
    {
        this.InitializeComponent();
    } //Win32Form1

    /** @attribute System.STAThreadAttribute()
     */
    public static void main(String[]
 args)
    {
        System.Windows.Forms.Application.Run(new Win32Form1());
    } //main
    
    private void InitializeComponent()
    {
        this.addButton = new System.Windows.Forms.Button();
        this.textBox2 = new System.Windows.Forms.TextBox();
        this.addGrandButton = new System.Windows.Forms.Button();
        this.comboBox1 = new System.Windows.Forms.ComboBox();
        this.showSelectedButton = new System.Windows.Forms.Button();
        this.textBox1 = new System.Windows.Forms.TextBox();
        this.findButton = new System.Windows.Forms.Button();
        this.label1 = new System.Windows.Forms.Label();
        this.addButton.set_Location(new System.Drawing.Point(248,
 32));
        this.addButton.set_Size(new System.Drawing.Size(40,
 24));
        this.addButton.set_TabIndex(1);
        this.addButton.set_Text("Add");
        this.addButton.add_Click(new System.EventHandler(this.addButton_Click));
        this.textBox2.set_Location(new System.Drawing.Point(8,
 64));
        this.textBox2.set_Size(new System.Drawing.Size(232,
 20));
        this.textBox2.set_TabIndex(6);
        this.textBox2.set_Text("");
        this.addGrandButton.set_Location(new
 System.Drawing.Point(8, 96));
        this.addGrandButton.set_Size(new System.Drawing.Size(280,
 23));
        this.addGrandButton.set_TabIndex(2);
        this.addGrandButton.set_Text("Add 1,000 Items");
        this.addGrandButton.add_Click(new System.EventHandler(
            this.addGrandButton_Click));
        this.comboBox1.set_Anchor(System.Windows.Forms.AnchorStyles.Bottom
            | System.Windows.Forms.AnchorStyles.Left
            | System.Windows.Forms.AnchorStyles.Right);
        this.comboBox1.set_DropDownWidth(280);
        this.comboBox1.get_Items().AddRange(new
 Object[] 
            { "Item 1", "Item 2", "Item 3", "Item
 4", "Item 5" });
        this.comboBox1.set_Location(new System.Drawing.Point(8,
 248));
        this.comboBox1.set_Size(new System.Drawing.Size(280,
 21));
        this.comboBox1.set_TabIndex(7);
        this.showSelectedButton.set_Location(new
 System.Drawing.Point(8, 128));
        this.showSelectedButton.set_Size(new
 System.Drawing.Size(280, 24));
        this.showSelectedButton.set_TabIndex(4);
        this.showSelectedButton.set_Text("What Item is Selected?");
        this.showSelectedButton.add_Click(new
 System.EventHandler(
            this.showSelectedButton_Click));
        this.textBox1.set_Location(new System.Drawing.Point(8,
 32));
        this.textBox1.set_Size(new System.Drawing.Size(232,
 20));
        this.textBox1.set_TabIndex(5);
        this.textBox1.set_Text("");
        this.findButton.set_Location(new System.Drawing.Point(248,
 64));
        this.findButton.set_Size(new System.Drawing.Size(40,
 24));
        this.findButton.set_TabIndex(3);
        this.findButton.set_Text("Find");
        this.findButton.add_Click(new System.EventHandler(
            this.findButton_Click));
        this.label1.set_Location(new System.Drawing.Point(8,
 224));
        this.label1.set_Size(new System.Drawing.Size(144,
 23));
        this.label1.set_TabIndex(0);
        this.label1.set_Text("Test ComboBox");
        this.set_ClientSize(new System.Drawing.Size(292,
 273));
        this.get_Controls().AddRange(new System.Windows.Forms.Control[]
            { this.comboBox1, this.textBox2,
 this.textBox1,
            this.showSelectedButton, this.findButton,
 this.addGrandButton,
            this.addButton, this.label1 });
        this.set_Text("ComboBox Sample");
    } //InitializeComponent

    private void addButton_Click(Object sender,
 System.EventArgs e)
    {
        comboBox1.get_Items().Add(textBox1.get_Text());
    } //addButton_Click

    private void addGrandButton_Click(Object
 sender, System.EventArgs e)
    {
        comboBox1.BeginUpdate();
        for (int i = 0; i < 1000; i++) {
            comboBox1.get_Items().Add("Item 1" + ((Int32)i).ToString());
        }
        comboBox1.EndUpdate();
    } //addGrandButton_Click

    private void findButton_Click(Object sender,
 System.EventArgs e)
    {
        int index = comboBox1.FindString(textBox2.get_Text());
        comboBox1.set_SelectedIndex(index);
    } //findButton_Click

    private void showSelectedButton_Click(Object
 sender, System.EventArgs e)
    {
        int selectedIndex = comboBox1.get_SelectedIndex();
        Object selectedItem = comboBox1.get_SelectedItem();
        MessageBox.Show("Selected Item Text: " + selectedItem.ToString()
 
            + "\n" + "Index: " + ((Int32)selectedIndex).ToString());
    } //showSelectedButton_Click

Public Sub New

Dim instance As New ComboBox

public ComboBox ()

public:
ComboBox ()

public ComboBox ()

public function ComboBox ()