ScrollEventHandler 委托

表示处理 DataGridView、ScrollBar、TrackBar 或 DataGrid 的 Scroll 事件的方法。

**命名空间:**System.Windows.Forms
**程序集:**System.Windows.Forms（在 system.windows.forms.dll 中）

语法

声明
Public Delegate Sub ScrollEventHandler ( _
    sender As Object, _
    e As ScrollEventArgs _
)
用法
Dim instance As New ScrollEventHandler(AddressOf HandlerMethod)

public delegate void ScrollEventHandler (
    Object sender,
    ScrollEventArgs e
)

public delegate void ScrollEventHandler (
    Object^ sender, 
    ScrollEventArgs^ e
)

/** @delegate */
public delegate void ScrollEventHandler (
    Object sender, 
    ScrollEventArgs e
)

JScript 支持使用委托，但不支持进行新的声明。

参数

• sender
  事件源。

• e
  包含事件数据的 ScrollEventArgs。

备注

当创建 ScrollEventArgs 委托时，将标识处理事件的方法。若要使该事件与事件处理程序相关联，请将该委托的一个实例添加到事件中。除非移除了该委托，否则每当发生该事件时就调用事件处理程序。有关事件处理程序委托的更多信息，请参见 事件和委托。

示例

Private Sub AddMyScrollEventHandlers()
    ' Create and initialize a VScrollBar.
    Dim vScrollBar1 As New VScrollBar()
    
    ' Add event handlers for the OnScroll and OnValueChanged events.
    AddHandler vScrollBar1.Scroll, AddressOf Me.vScrollBar1_Scroll
    AddHandler vScrollBar1.ValueChanged, AddressOf Me.vScrollBar1_ValueChanged
End Sub    

' Create the ValueChanged event handler.
Private Sub vScrollBar1_ValueChanged(sender As Object, e As EventArgs)
    ' Display the new value in the label.
    label1.Text = "vScrollBar Value:(OnValueChanged Event) " & _
        vScrollBar1.Value.ToString()
End Sub    

' Create the Scroll event handler.
Private Sub vScrollBar1_Scroll(sender As Object, e As ScrollEventArgs)
    ' Display the new value in the label.
    label1.Text = "VScrollBar Value:(OnScroll Event) " & _
        e.NewValue.ToString()
End Sub    

Private Sub button1_Click(sender As Object, e As EventArgs)
    ' Add 40 to the Value property if it will not exceed the Maximum value.
    If vScrollBar1.Value + 40 < vScrollBar1.Maximum Then
        vScrollBar1.Value = vScrollBar1.Value + 40
    End If
End Sub

private void AddMyScrollEventHandlers()
 {
    // Create and initialize a VScrollBar.
    VScrollBar vScrollBar1 = new VScrollBar();
 
    // Add event handlers for the OnScroll and OnValueChanged events.
    vScrollBar1.Scroll += new ScrollEventHandler(
       this.vScrollBar1_Scroll);
    vScrollBar1.ValueChanged += new EventHandler(
       this.vScrollBar1_ValueChanged); 
 }
 
 // Create the ValueChanged event handler.
 private void vScrollBar1_ValueChanged(Object sender, 
                                       EventArgs e)
 {
     // Display the new value in the label.
     label1.Text = "vScrollBar Value:(OnValueChanged Event) " + vScrollBar1.Value.ToString();
 }
 
 // Create the Scroll event handler.
 private void vScrollBar1_Scroll(Object sender, 
                                 ScrollEventArgs e)
 {
     // Display the new value in the label.
     label1.Text = "VScrollBar Value:(OnScroll Event) " + e.NewValue.ToString();
 }
 
 private void button1_Click(Object sender, 
                           EventArgs e)
 {
    // Add 40 to the Value property if it will not exceed the Maximum value.
    if (vScrollBar1.Value + 40 < vScrollBar1.Maximum)
    {
        vScrollBar1.Value = vScrollBar1.Value + 40;
    }
 }
 

void AddMyScrollEventHandlers()
{
   // Create and initialize a VScrollBar.
   VScrollBar^ vScrollBar1 = gcnew VScrollBar;

   // Add event handlers for the OnScroll and OnValueChanged events.
   vScrollBar1->Scroll += gcnew ScrollEventHandler( this, &Form1::vScrollBar1_Scroll );
   vScrollBar1->ValueChanged += gcnew EventHandler( this, &Form1::vScrollBar1_ValueChanged );
}

// Create the ValueChanged event handler.
void vScrollBar1_ValueChanged( Object^ /*sender*/, EventArgs^ /*e*/ )
{
   // Display the new value in the label.
   label1->Text = String::Format( "vScrollBar Value:(OnValueChanged Event) {0}", vScrollBar1->Value );
}

// Create the Scroll event handler.
void vScrollBar1_Scroll( Object^ /*sender*/, ScrollEventArgs^ e )
{
   // Display the new value in the label.
   label1->Text = String::Format( "VScrollBar Value:(OnScroll Event) {0}", e->NewValue );
}

void button1_Click( Object^ /*sender*/, EventArgs^ /*e*/ )
{
   // Add 40 to the Value property if it will not exceed the Maximum value.
   if ( vScrollBar1->Value + 40 < vScrollBar1->Maximum )
   {
      vScrollBar1->Value = vScrollBar1->Value + 40;
   }
}

private void AddMyScrollEventHandlers()
{
    // Create and initialize a VScrollBar.
    VScrollBar vScrollBar1 = new VScrollBar();

    // Add event handlers for the OnScroll and OnValueChanged events.
    vScrollBar1.add_Scroll(
        new ScrollEventHandler(this.vScrollBar1_Scroll));
    vScrollBar1.add_ValueChanged(
        new EventHandler(this.vScrollBar1_ValueChanged));
} //AddMyScrollEventHandlers

// Create the ValueChanged event handler.
private void vScrollBar1_ValueChanged(Object sender, EventArgs e)
{
    // Display the new value in the label.
    label1.set_Text("vScrollBar Value:(OnValueChanged Event) " 
        + vScrollBar1.get_Value());
} //vScrollBar1_ValueChanged

// Create the Scroll event handler.
private void vScrollBar1_Scroll(Object sender, ScrollEventArgs e)
{
    // Display the new value in the label.
    label1.set_Text(
        "VScrollBar Value:(OnScroll Event) " + e.get_NewValue());
} //vScrollBar1_Scroll

private void button1_Click(Object sender, EventArgs e)
{
    // Add 40 to the Value property if it will not exceed the Maximum 
    // value.
    if (vScrollBar1.get_Value() + 40 < vScrollBar1.get_Maximum()) {
        vScrollBar1.set_Value(vScrollBar1.get_Value() + 40);
    }
} //button1_Click

平台

Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition

.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。

版本信息

.NET Framework

受以下版本支持：2.0、1.1、1.0

请参见

参考

System.Windows.Forms 命名空间
DataGridView 类
ScrollBar 类
TrackBar
DataGrid 类