TrackBar.SmallChange Eigenschap
Definitie
Belangrijk
Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.
Hiermee haalt u de toegevoegde waarde op of trekt u deze af van de Value eigenschap wanneer het schuifvak een kleine afstand wordt verplaatst.
public:
property int SmallChange { int get(); void set(int value); };
public int SmallChange { get; set; }
member this.SmallChange : int with get, set
Public Property SmallChange As Integer
Waarde van eigenschap
Een numerieke waarde. De standaardwaarde is 1.
Uitzonderingen
De toegewezen waarde is kleiner dan 0.
Voorbeelden
In het volgende codevoorbeeld wordt een formulier weergegeven dat een TrackBar besturingselement en een TextBox besturingselement bevat. In het voorbeeld ziet u hoe u de Maximum, TickFrequencyen LargeChangeeigenschappen instelt SmallChange en de Scroll gebeurtenis verwerkt. De TextBox inhoud wordt bijgewerkt naar de Value eigenschapswaarde wanneer de Scroll gebeurtenis plaatsvindt.
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
Opmerkingen
Wanneer de gebruiker op een van de pijltoetsen drukt, wordt de Value eigenschap gewijzigd op basis van de waarde die in de SmallChange eigenschap is ingesteld.
U kunt overwegen om de waarde in te stellen op SmallChange een percentage van de waarde van de Height eigenschap (voor een verticaal georiënteerde trackbalk) of Width (voor een horizontaal georiënteerde trackbalk). Hiermee stelt u de afstand in die uw trackbalk evenredig is met de grootte.