TrackBar.LargeChange Propiedad

Definición

Espacio de nombres:

System.Windows.Forms

Ensamblado:

System.Windows.Forms.dll

Obtiene o establece un valor que se suma o se resta de la propiedad Value cuando el cuadro de desplazamiento se mueve una distancia grande.

public:
 property int LargeChange { int get(); void set(int value); };

public int LargeChange { get; set; }

member this.LargeChange : int with get, set

Public Property LargeChange As Integer

Valor de propiedad

Int32

Valor numérico. El valor predeterminado es 5.

Excepciones

ArgumentException

El valor asignado es menor que 0.

Ejemplos

En el ejemplo de código siguiente se muestra un formulario que contiene un TrackBar control y un TextBox control . En el ejemplo se muestra cómo establecer las Maximumpropiedades , TickFrequency, LargeChangey y SmallChange controlar el Scroll evento. El TextBox contenido se actualiza al valor de propiedad Value cuando se produce el Scroll evento.

using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
public ref class Form1: public System::Windows::Forms::Form
{
private:
   System::Windows::Forms::TrackBar^ trackBar1;
   System::Windows::Forms::TextBox^ textBox1;

public:
   Form1()
   {
      this->textBox1 = gcnew System::Windows::Forms::TextBox;
      this->trackBar1 = gcnew System::Windows::Forms::TrackBar;
      
      // TextBox for TrackBar::Value update.
      this->textBox1->Location = System::Drawing::Point( 240, 16 );
      this->textBox1->Size = System::Drawing::Size( 48, 20 );
      
      // Set up how the form should be displayed and add the controls to the form.
      this->ClientSize = System::Drawing::Size( 296, 62 );
      array<System::Windows::Forms::Control^>^formControls = {this->textBox1,this->trackBar1};
      this->Controls->AddRange( formControls );
      this->Text = "TrackBar Example";
      
      // Set up the TrackBar.
      this->trackBar1->Location = System::Drawing::Point( 8, 8 );
      this->trackBar1->Size = System::Drawing::Size( 224, 45 );
      this->trackBar1->Scroll += gcnew System::EventHandler( this, &Form1::trackBar1_Scroll );
      
      // The Maximum property sets the value of the track bar when
      // the slider is all the way to the right.
      trackBar1->Maximum = 30;
      
      // The TickFrequency property establishes how many positions
      // are between each tick-mark.
      trackBar1->TickFrequency = 5;
      
      // The LargeChange property sets how many positions to move
      // if the bar is clicked on either side of the slider.
      trackBar1->LargeChange = 3;
      
      // The SmallChange property sets how many positions to move
      // if the keyboard arrows are used to move the slider.
      trackBar1->SmallChange = 2;
   }


private:
   void trackBar1_Scroll( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      
      // Display the trackbar value in the text box.
      textBox1->Text = String::Concat( "", trackBar1->Value );
   }

};


[STAThread]
int main()
{
   Application::Run( gcnew Form1 );
}

using System;
using System.Drawing;
using System.Windows.Forms;

public class Form1 : System.Windows.Forms.Form
{
    private System.Windows.Forms.TrackBar trackBar1;
    private System.Windows.Forms.TextBox textBox1;

    [STAThread]
    static void Main() 
    {
        Application.Run(new Form1());
    }

    public Form1()
    {
        this.textBox1 = new System.Windows.Forms.TextBox();
        this.trackBar1 = new System.Windows.Forms.TrackBar();

        // TextBox for TrackBar.Value update.
        this.textBox1.Location = new System.Drawing.Point(240, 16);
        this.textBox1.Size = new System.Drawing.Size(48, 20);

        // Set up how the form should be displayed and add the controls to the form.
        this.ClientSize = new System.Drawing.Size(296, 62);
        this.Controls.AddRange(new System.Windows.Forms.Control[] {this.textBox1,this.trackBar1});
        this.Text = "TrackBar Example";

        // Set up the TrackBar.
        this.trackBar1.Location = new System.Drawing.Point(8, 8);
        this.trackBar1.Size = new System.Drawing.Size(224, 45);
        this.trackBar1.Scroll += new System.EventHandler(this.trackBar1_Scroll);

        // The Maximum property sets the value of the track bar when
        // the slider is all the way to the right.
        trackBar1.Maximum = 30;
        
        // The TickFrequency property establishes how many positions
        // are between each tick-mark.
        trackBar1.TickFrequency = 5;

        // The LargeChange property sets how many positions to move
        // if the bar is clicked on either side of the slider.
        trackBar1.LargeChange = 3;

        // The SmallChange property sets how many positions to move
        // if the keyboard arrows are used to move the slider.
        trackBar1.SmallChange = 2;
    }

    private void trackBar1_Scroll(object sender, System.EventArgs e)
    {
        // Display the trackbar value in the text box.
        textBox1.Text = "" + trackBar1.Value;
    }
}

Imports System.Drawing
Imports System.Windows.Forms

Public Class Form1
    Inherits System.Windows.Forms.Form

    Private WithEvents trackBar1 As System.Windows.Forms.TrackBar
    Private textBox1 As System.Windows.Forms.TextBox

    <System.STAThread()> _
    Public Shared Sub Main()
        System.Windows.Forms.Application.Run(New Form1)
    End Sub

    Public Sub New()
        Me.textBox1 = New System.Windows.Forms.TextBox
        Me.trackBar1 = New System.Windows.Forms.TrackBar

        ' TextBox for TrackBar.Value update.
        Me.textBox1.Location = New System.Drawing.Point(240, 16)
        Me.textBox1.Size = New System.Drawing.Size(48, 20)

        ' Set up how the form should be displayed and add the controls to the form.
        Me.ClientSize = New System.Drawing.Size(296, 62)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.textBox1, Me.trackBar1})
        Me.Text = "TrackBar Example"

        ' Set up the TrackBar.
        Me.trackBar1.Location = New System.Drawing.Point(8, 8)
        Me.trackBar1.Size = New System.Drawing.Size(224, 45)

        ' The Maximum property sets the value of the track bar when
        ' the slider is all the way to the right.
        trackBar1.Maximum = 30

        ' The TickFrequency property establishes how many positions
        ' are between each tick-mark.
        trackBar1.TickFrequency = 5

        ' The LargeChange property sets how many positions to move
        ' if the bar is clicked on either side of the slider.
        trackBar1.LargeChange = 3

        ' The SmallChange property sets how many positions to move
        ' if the keyboard arrows are used to move the slider.
        trackBar1.SmallChange = 2
    End Sub

    Private Sub trackBar1_Scroll(ByVal sender As Object, _
                    ByVal e As System.EventArgs) Handles trackBar1.Scroll

        ' Display the trackbar value in the text box.
        textBox1.Text = trackBar1.Value
    End Sub 

End Class

Comentarios

Cuando el usuario presiona la tecla PAGE UP o PAGE DOWN o hace clic en la barra de seguimiento de cualquier lado del cuadro de desplazamiento, la Value propiedad cambia según el valor establecido en la LargeChange propiedad . Puede considerar la posibilidad de establecer el LargeChange valor en un porcentaje de Height (para una barra de seguimiento orientada verticalmente) o Width (para un valor de barra de seguimiento orientada horizontalmente). Esto mantiene la distancia a la que se mueve la barra de seguimiento proporcional a su tamaño.