HtmlInputImage.OnServerClick(ImageClickEventArgs) 方法
定义
引发 ServerClick 事件。Raises the ServerClick event.
protected:
virtual void OnServerClick(System::Web::UI::ImageClickEventArgs ^ e);
protected virtual void OnServerClick (System.Web.UI.ImageClickEventArgs e);
abstract member OnServerClick : System.Web.UI.ImageClickEventArgs -> unit
override this.OnServerClick : System.Web.UI.ImageClickEventArgs -> unit
Protected Overridable Sub OnServerClick (e As ImageClickEventArgs)
参数
包含事件数据的 ImageClickEventArgs。An ImageClickEventArgs that contains event data.
示例
下面的代码示例演示如何为事件指定和编写处理程序, ServerClick 以确定用户单击控件的位置的坐标 HtmlInputImage 。The following code example demonstrates how to specify and code a handler for the ServerClick event to determine the coordinates where the user clicks the HtmlInputImage control.
<%@ Page Language="C#" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
protected void ImageBtn_Click(object sender, ImageClickEventArgs e)
{
// Write the click coordinates to the Span1 element.
Span1.InnerText = "You clicked at (" + e.X.ToString() +
", " + e.Y.ToString() + ").";
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Click the Image </title>
</head>
<body>
<form id="form1" runat="server">
<h3>Click the Image </h3>
<input type="image"
alt="Image Alternate Text"
src="Image1.jpg"
onserverclick="ImageBtn_Click"
runat="server" id="Image1"/>
<br />
<br />
<span id="Span1"
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub ImageBtn_Click(ByVal Sender As Object, ByVal E As ImageClickEventArgs)
' Write the click coordinates to the Span1 element.
Span1.InnerText = "You clicked at (" & E.X.ToString() & _
", " & E.Y.ToString() & ")."
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Click the Image </title>
</head>
<body>
<form id="form1" runat="server">
<h3>Click the Image </h3>
<input type="image"
alt="Image Alternate Text"
src="Image1.jpg"
onserverclick="ImageBtn_Click"
runat="server"/>
<br />
<br />
<span id="Span1"
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void ImageBtn_Click(Object sender, ImageClickEventArgs e)
{
// Display the coordinates of the position where the image
// was clicked.
Span1.InnerText = "You clicked at (" + e.X.ToString() +
", " + e.Y.ToString() + ").";
}
void Page_Load(Object sender, EventArgs e)
{
// Create an EventHandler delegate for the method you want to
// handle the event, and then add it to the list of methods called
// when the event is raised.
Image1.ServerClick += new ImageClickEventHandler(this.ImageBtn_Click);
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>HtmlInputImage ServerClick Example </title>
</head>
<body>
<form id="form1" runat="server">
<h3>HtmlInputImage ServerClick Example </h3>
<input type="image"
id="Image1"
src="Image.jpg"
alt="Image"
runat="server"/>
<br />
<span id="Span1"
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub ImageBtn_Click(ByVal sender As Object, ByVal e As ImageClickEventArgs)
' Display the coordinates of the position where the image
' was clicked.
Span1.InnerText = "You clicked at (" & e.X.ToString() & _
", " & e.Y.ToString() & ")."
End Sub
Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Create an EventHandler delegate for the method you want to
' handle the event, and then add it to the list of methods called
' when the event is raised.
AddHandler Image1.ServerClick, AddressOf ImageBtn_Click
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>HtmlInputImage ServerClick Example </title>
</head>
<body>
<form id="form1" runat="server">
<h3>HtmlInputImage ServerClick Example </h3>
<input type="image"
id="Image1"
src="Image.jpg"
alt="Image"
runat="server"/>
<br />
<span id="Span1"
runat="server"/>
</form>
</body>
</html>
注解
ServerClick当用户单击控件时,将引发事件 HtmlInputImage 。The ServerClick event is raised when the user clicks an HtmlInputImage control.
用户单击控件的位置的坐标 HtmlInputImage 可以使用 ImageClickEventArgs.X 对象的和属性来确定 ImageClickEventArgs.Y System.Web.UI.ImageClickEventArgs 。The coordinates where the user clicks an HtmlInputImage control can be determined by using the ImageClickEventArgs.X and ImageClickEventArgs.Y properties of the System.Web.UI.ImageClickEventArgs object. System.Web.UI.ImageClickEventArgs对象作为参数传递给用户定义的事件处理程序。The System.Web.UI.ImageClickEventArgs object is passed as a parameter to the user-defined event handler.
备注
原点 (0,0) 位于图像的左上角。The origin (0, 0) is located at the upper-left corner of the image.
引发事件时,将通过委托调用事件处理程序。Raising an event invokes the event handler through a delegate. 有关详细信息,请参阅 处理和引发事件。For more information, see Handling and Raising Events.
OnServerClick 方法还允许派生类对事件进行处理而不必附加委托。The OnServerClick method also allows derived classes to handle the event without attaching a delegate. 这是在派生类中处理事件的首选技术。This is the preferred technique for handling the event in a derived class.
继承者说明
在派生类中重写 OnServerClick(ImageClickEventArgs) 时,一定要调用基类的 OnServerClick(ImageClickEventArgs) 方法,以便已注册的委托对事件进行接收。When overriding OnServerClick(ImageClickEventArgs) in a derived class, be sure to call the base class's OnServerClick(ImageClickEventArgs) method so that registered delegates receive the event.