DataGridViewCheckBoxCell.FalseValue Propiedad

Definición

Espacio de nombres:

System.Windows.Forms

Ensamblado:

System.Windows.Forms.dll

Obtiene o establece el valor subyacente que corresponde a un valor de celda de false.

public:
 property System::Object ^ FalseValue { System::Object ^ get(); void set(System::Object ^ value); };

public object FalseValue { get; set; }

member this.FalseValue : obj with get, set

Public Property FalseValue As Object

Valor de propiedad

Object

Un Object que corresponde a un valor de celda de false. De manera predeterminada, es null.

Ejemplos

En el ejemplo de código siguiente se usa un DataGridViewCheckBoxCell para realizar un seguimiento del estado de la iluminación de la oficina. La FalseValue propiedad asocia "turnedOff" a false, la TrueValue propiedad asocia "turnedOn" con truey la IndeterminateValue propiedad asocia "unknown" a indeterminado.

#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

Comentarios

Las FalseValuepropiedades , TrueValuey IndeterminateValue determinan los valores asociados de estos estados a medida que se producen en el origen de datos subyacente.

Si se establece la FalseValue propiedad de la columna propietaria, también se establece la FalseValue propiedad de cada celda de la columna y se actualiza la presentación de la columna. Para invalidar el valor especificado para celdas individuales, establezca los valores de celda después de establecer el valor de columna.

Consulte también

• DataGridView
• FalseValue
• TrueValue
• IndeterminateValue