更新：2007 年 11 月
命名空间：
System.Web.Configuration 程序集：
System.Web（在 System.Web.dll 中）
Public Overridable ReadOnly Property SupportsCallback As Boolean
Dim instance As HttpCapabilitiesBase
Dim value As Boolean
value = instance.SupportsCallback
public virtual bool SupportsCallback { get; }
public:
virtual property bool SupportsCallback {
bool get ();
}
/** @property */
public boolean get_SupportsCallback()
public function get SupportsCallback () : boolean
下面的代码示例演示如何确定浏览器是否支持回调脚本。
<%@ page language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
CheckBrowserCaps()
End Sub
Function CheckBrowserCaps()
Dim labelText As String = ""
Dim myBrowserCaps As System.Web.HttpBrowserCapabilities = Request.Browser
If (CType(myBrowserCaps, System.Web.Configuration.HttpCapabilitiesBase)).SupportsCallback Then
labelText = "Browser supports callback scripts."
Else
labelText = "Browser does not support callback scripts."
End If
Label1.Text = labelText
End Function 'CheckBrowserCaps
</script>
<html >
<head>
<title>Browser Capabilities Sample</title>
</head>
<body>
<form runat="server" id="form1">
<div>
Browser Capabilities:
<p/><asp:Label ID="Label1" Runat="server" />
</div>
</form>
</body>
</html>
<%@ page language="C#"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void Page_Load(Object Sender, EventArgs e)
{
CheckBrowserCaps();
}
void CheckBrowserCaps()
{
String labelText = "";
System.Web.HttpBrowserCapabilities myBrowserCaps = Request.Browser;
if (((System.Web.Configuration.HttpCapabilitiesBase)myBrowserCaps).SupportsCallback)
{
labelText = "Browser supports callback scripts.";
}
else
{
labelText = "Browser does not support callback scripts.";
}
Label1.Text = labelText;
}
</script>
<html >
<head>
<title>Browser Capabilities Sample</title>
</head>
<body>
<form runat="server" id="form1">
<div>
Browser Capabilities:
<p/><asp:Label ID="Label1" Runat="server" />
</div>
</form>
</body>
</html>
<%@ page language="VJ#"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void Page_Load(Object sender, EventArgs e)
{
CheckBrowserCaps();
} //Page_Load
void CheckBrowserCaps()
{
String labelText = "";
System.Web.HttpBrowserCapabilities myBrowserCaps =
get_Request().get_Browser();
if (((System.Web.Configuration.HttpCapabilitiesBase)myBrowserCaps).
get_SupportsCallback()) {
labelText = "Browser supports callback scripts.";
}
else {
labelText = "Browser does not support callback scripts.";
}
Label1.set_Text(labelText);
} //CheckBrowserCaps
</script>
<html >
<head>
<title>Browser Capabilities Sample</title>
</head>
<body>
<form runat="server" id="form1">
<div>
Browser Capabilities:
<p/><asp:Label ID="Label1" Runat="server" />
</div>
</form>
</body>
</html>
Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
.NET Framework 和 .NET Compact Framework 并不是对每个平台的所有版本都提供支持。有关支持的版本的列表，请参见.NET Framework 系统要求。
.NET Framework
受以下版本支持：3.5、3.0、2.0
参考