TemplateControl 类

定义

public ref class TemplateControl abstract : System::Web::UI::Control, System::Web::UI::INamingContainer

public ref class TemplateControl abstract : System::Web::UI::Control, System::Web::UI::IFilterResolutionService, System::Web::UI::INamingContainer

public abstract class TemplateControl : System.Web.UI.Control, System.Web.UI.INamingContainer

public abstract class TemplateControl : System.Web.UI.Control, System.Web.UI.IFilterResolutionService, System.Web.UI.INamingContainer

type TemplateControl = class
    inherit Control
    interface INamingContainer

type TemplateControl = class
    inherit Control
    interface INamingContainer
    interface IFilterResolutionService

Public MustInherit Class TemplateControl
Inherits Control
Implements INamingContainer

Public MustInherit Class TemplateControl
Inherits Control
Implements IFilterResolutionService, INamingContainer

继承

Object

Control

TemplateControl

派生

System.Web.UI.Page

System.Web.UI.UserControl

实现

INamingContainer IFilterResolutionService

示例

下面的代码示例演示如何派生从类命名 MyControl 的 TemplateControl 控件并重写 Construct 方法。 初始化时 MyControl ，将调用重写 Construct 的方法。

using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Security.Permissions;

// The custom user control class.
[AspNetHostingPermission(SecurityAction.Demand,
   Level = AspNetHostingPermissionLevel.Minimal)]
public class MyControl : UserControl
{
    // Create a Message property and accessors.
    private string _message = "No message";

    public string Message
    {
        get { return _message; }
        set { _message = value; }
    }

    // Create an event for this user control
    public event System.EventHandler myControl;

    // Override the default constructor.
    protected override void Construct()
    {
        // Specify the handler for the OnInit method.
        this.myControl += new EventHandler(MyInit);
    }

    protected override void OnInit(EventArgs e)
    {
        myControl(this, e);
        Response.Write("The OnInit() method is used to raise the Init event.");
    }

    // Use the MyInit handler to set the Message property
    void MyInit(object sender, System.EventArgs e)
    {
        Message = "Hello World!";
    }

    // Render the value of the Message property
    protected override void Render(HtmlTextWriter writer)
    {
        writer.Write("<br>Message :" + Message);
    }
}

Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Security.Permissions

' The custom user control class.
<AspNetHostingPermission(SecurityAction.Demand, _
   Level:=AspNetHostingPermissionLevel.Minimal)> _
Public Class MyControl
   Inherits UserControl
   ' Create a Message property and accessors.
   Private _message As String = Nothing
   
   Public Property Message() As String
      Get
         Return _message
      End Get
      Set
         _message = value
      End Set
   End Property
   
    ' Create an event for this user control
    Public Event myControl As System.EventHandler

    ' Override the default constructor.
    Protected Overrides Sub Construct()
        ' Specify the handler for the OnInit method.
        AddHandler Me.myControl, AddressOf MyInit
    End Sub

    Protected Overrides Sub OnInit(ByVal e As EventArgs)
        RaiseEvent myControl(Me, e)
        Response.Write("The OnInit() method is used to raise the Init event.")
    End Sub
   
   
    ' Use the MyInit handler to set the Message property
    Sub MyInit(ByVal sender As Object, ByVal e As System.EventArgs)
        Message = "Hello World!"
    End Sub
   
    ' Render the value of the Message property
    Protected Overrides Sub Render(ByVal writer As HtmlTextWriter)
        writer.Write(("<br>Message :" & Message))
    End Sub
End Class

注解

该 TemplateControl 类是一个抽象类，它 Page 为类和类提供通用属性和 UserControl 方法。 不会直接创建该实例的新实例 TemplateControl 。

该 TemplateControl 类定义支持声明性数据绑定表达式的方法：

• 使用 Eval 涉及数据源的数据绑定表达式的方法，例如简单属性或表达式。

• 使用该方法 XPath 分析和计算 XPath 数据绑定表达式。

• 对 XPathSelect 包含 XPath select 语句的表达式使用数据绑定方法。 结果是实现接口的 IEnumerable 节点集合。

有关数据绑定表达式的详细信息，请参阅 Data-Binding 表达式语法 和 绑定到数据库。

另请参阅

• Page
• UserControl