DataGridViewCheckBoxCell.ThreeState プロパティ

定義

ホストされているチェック ボックス コントロールの 3 進モードが有効になっているかどうかを示す値を取得または設定します。Gets or sets a value indicating whether ternary mode has been enabled for the hosted check box control.

public:
 property bool ThreeState { bool get(); void set(bool value); };
public bool ThreeState { get; set; }
member this.ThreeState : bool with get, set
Public Property ThreeState As Boolean

プロパティ値

3 進モードが有効な場合は true。2 進モードが有効な場合は falsetrue if ternary mode is enabled; false if binary mode is enabled. 既定値は、false です。The default is false.

次のコード例ではDataGridViewCheckBoxCell 、を使用して、オフィスの照明の状態を追跡します。The following code example uses a DataGridViewCheckBoxCell to track the status of office lighting. TrueValue false IndeterminateValue trueプロパティによって "turnedOff" がに関連付けられ、プロパティによって "turnedon" がに関連付けられ、プロパティによって "unknown" が未確定に関連付けられます。 FalseValueThe FalseValue property associates "turnedOff" with false, the TrueValue property associates "turnedOn" with true, and the IndeterminateValue property associates "unknown" to indeterminate.

#using <System.Windows.Forms.dll>
#using <System.dll>
#using <System.Drawing.dll>
using namespace System;
using namespace System::IO;
using namespace System::Collections::Generic;
using namespace System::Windows::Forms;

public enum class LightStatus
{
    Unknown,
    TurnedOn,
    TurnedOff
};

public ref class TriValueVirtualCheckBox: public Form
{
private:
    DataGridView^ dataGridView1;

private:
    const int initialSize;

private:
    Dictionary<int, LightStatus>^ store;

public:
    TriValueVirtualCheckBox() :  Form(), initialSize(500)
    {
        dataGridView1 = gcnew DataGridView();
        store = gcnew Dictionary<int, LightStatus>();
        Text = this->GetType()->Name;

        for(int i = 0; i < initialSize; i++)
        {
            store->Add(i, LightStatus::Unknown);
        }

        Controls->Add(dataGridView1);
        dataGridView1->VirtualMode = true;
        dataGridView1->AllowUserToDeleteRows = false;
        dataGridView1->CellValueNeeded += 
            gcnew DataGridViewCellValueEventHandler(
            this, &TriValueVirtualCheckBox::dataGridView1_CellValueNeeded);
        dataGridView1->CellValuePushed += 
            gcnew DataGridViewCellValueEventHandler(
            this, &TriValueVirtualCheckBox::dataGridView1_CellValuePushed);

        dataGridView1->Columns->Add(CreateCheckBoxColumn());
        dataGridView1->Rows->AddCopies(0, initialSize);
    }

private:
    DataGridViewCheckBoxColumn^ CreateCheckBoxColumn()
    {
        DataGridViewCheckBoxColumn^ dataGridViewCheckBoxColumn1
            = gcnew DataGridViewCheckBoxColumn();
        dataGridViewCheckBoxColumn1->HeaderText = "Lights On";
        dataGridViewCheckBoxColumn1->TrueValue = LightStatus::TurnedOn;
        dataGridViewCheckBoxColumn1->FalseValue =
            LightStatus::TurnedOff;
        dataGridViewCheckBoxColumn1->IndeterminateValue
            = LightStatus::Unknown;
        dataGridViewCheckBoxColumn1->ThreeState = true;
        dataGridViewCheckBoxColumn1->ValueType = LightStatus::typeid;
        return dataGridViewCheckBoxColumn1;
    }

#pragma region "data store maintance"
private:
    void dataGridView1_CellValueNeeded(Object^ sender,
        DataGridViewCellValueEventArgs^ e)
    {
        e->Value = store[e->RowIndex];
    }

private:
    void dataGridView1_CellValuePushed(Object^ sender,
        DataGridViewCellValueEventArgs^ e)
    {
        store[e->RowIndex] = (LightStatus) e->Value;
    }
#pragma endregion

};

[STAThread]
int main()
{
    Application::Run(gcnew TriValueVirtualCheckBox());
}

using System;
using System.IO;
using System.Collections.Generic;
using System.Windows.Forms;

public class TriValueVirtualCheckBox:Form
{
    DataGridView dataGridView1 = new DataGridView();

    const int initialSize = 500;

    Dictionary<int, LightStatus> store 
        = new Dictionary<int, LightStatus>();

    public TriValueVirtualCheckBox() : base()
    {        
        Text = this.GetType().Name;

        int index = 0;
        for(index=0; index<=initialSize; index++)
            store.Add(index, LightStatus.Unknown);

        Controls.Add(dataGridView1);
        dataGridView1.VirtualMode = true;
        dataGridView1.AllowUserToDeleteRows = false;
        dataGridView1.CellValueNeeded += new 
            DataGridViewCellValueEventHandler(dataGridView1_CellValueNeeded);
        dataGridView1.CellValuePushed += new 
            DataGridViewCellValueEventHandler(dataGridView1_CellValuePushed);

        dataGridView1.Columns.Add(CreateCheckBoxColumn());
        dataGridView1.Rows.AddCopies(0, initialSize);
    }

    private DataGridViewCheckBoxColumn CreateCheckBoxColumn()
    {
        DataGridViewCheckBoxColumn dataGridViewCheckBoxColumn1 
            = new DataGridViewCheckBoxColumn();
        dataGridViewCheckBoxColumn1.HeaderText = "Lights On";
        dataGridViewCheckBoxColumn1.TrueValue = LightStatus.TurnedOn;
        dataGridViewCheckBoxColumn1.FalseValue = LightStatus.TurnedOff;
        dataGridViewCheckBoxColumn1.IndeterminateValue 
            = LightStatus.Unknown;
        dataGridViewCheckBoxColumn1.ThreeState = true;
        dataGridViewCheckBoxColumn1.ValueType = typeof(LightStatus);
        return dataGridViewCheckBoxColumn1;
    }

#region "data store maintance"
    private void dataGridView1_CellValueNeeded(object sender, 
        DataGridViewCellValueEventArgs e)
    {
        e.Value = store[e.RowIndex];
    }

    private void dataGridView1_CellValuePushed(object sender, 
        DataGridViewCellValueEventArgs e)
    {
        store[e.RowIndex] = (LightStatus) e.Value;
    }
#endregion

    [STAThreadAttribute()]
    public static void Main()
    {
        Application.Run(new TriValueVirtualCheckBox());
    }
}

public enum LightStatus
{
    Unknown, 
    TurnedOn, 
    TurnedOff
};

Imports System.IO
Imports System.Collections.Generic
Imports System.Windows.Forms

Public Class TriValueVirtualCheckBox
    Inherits System.Windows.Forms.Form

    Dim WithEvents dataGridView1 As New DataGridView

    Const initialSize As Integer = 500

    Dim store As New Dictionary(Of Integer, LightStatus)

    Public Sub New()
        MyBase.New()
        Text = Me.GetType().Name

        Dim index As Integer = 0
        For index = 0 To initialSize
            store.Add(index, LightStatus.Unknown)
        Next

        Controls.Add(dataGridView1)
        dataGridView1.VirtualMode = True
        dataGridView1.AllowUserToDeleteRows = False
        dataGridView1.Columns.Add(CreateCheckBoxColumn())
        dataGridView1.Rows.AddCopies(0, initialSize)
    End Sub

    Private Function CreateCheckBoxColumn() As DataGridViewCheckBoxColumn
        Dim dataGridViewCheckBoxColumn1 _
            As New DataGridViewCheckBoxColumn()
        dataGridViewCheckBoxColumn1.HeaderText = "Lights On"
        dataGridViewCheckBoxColumn1.TrueValue = LightStatus.TurnedOn
        dataGridViewCheckBoxColumn1.FalseValue = LightStatus.TurnedOff
        dataGridViewCheckBoxColumn1.IndeterminateValue = _
            LightStatus.Unknown
        dataGridViewCheckBoxColumn1.ThreeState = True
        dataGridViewCheckBoxColumn1.ValueType = GetType(LightStatus)
        Return dataGridViewCheckBoxColumn1
    End Function

#Region "data store maintance"
    Private Sub dataGridView1_CellValueNeeded(ByVal sender As Object, _
        ByVal e As DataGridViewCellValueEventArgs) _
        Handles dataGridView1.CellValueNeeded

        e.Value = store(e.RowIndex)
    End Sub

    Private Sub dataGridView1_CellValuePushed(ByVal sender As Object, _
        ByVal e As DataGridViewCellValueEventArgs) _
        Handles dataGridView1.CellValuePushed

        store.Item(e.RowIndex) = CType(e.Value, LightStatus)
    End Sub
#End Region

    <STAThreadAttribute()> _
    Public Shared Sub Main()
        Application.Run(New TriValueVirtualCheckBox())
    End Sub
End Class

Public Enum LightStatus
    Unknown
    TurnedOn
    TurnedOff
End Enum

注釈

三項モードの3番目の状態は、通常、初期化されていない値または不確定の値を表します。The third state in ternary mode typically represents an uninitialized or indeterminate value.

所有している列のThreeState プロパティを設定すると、列のすべてのセルのプロパティも設定され、列の表示が更新されます。ThreeStateSetting the ThreeState property of the owning column also sets the ThreeState property of every cell in the column and refreshes the column display. 個々のセルに対して指定された値をオーバーライドするには、列の値を設定した後にセルの値を設定します。To override the specified value for individual cells, set the cell values after you set the column value.

Column ThreeStateプロパティとは異なり、セルThreeStateプロパティは、値を変更NullValueしたときに、関連付けられているセルスタイルのプロパティを自動的に更新しません。Unlike the column ThreeState property, the cell ThreeState property does not automatically update the NullValue property of the associated cell style when you change its value. セルThreeStateプロパティの値をにtrue変更する場合は、 StyleプロパティによっNullValueて返されるオブジェクトのプロパティをにIndeterminate設定します。When you change the cell ThreeState property value to true, be sure to set the NullValue property of the object returned by the Style property to Indeterminate. ThreeStateプロパティ値をにfalse変更する場合は、 NullValueプロパティをにfalse設定してください。When you change the ThreeState property value to false, be sure to set the NullValue property to false.

適用対象

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