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HttpCapabilitiesBase.SupportsCacheControlMetaTag Properti

Definisi

Ruang nama:
System.Web.Configuration
Rakitan:
System.Web.dll

Mendapatkan nilai yang menunjukkan apakah browser mendukung cache-control nilai untuk http-equiv atribut elemen HTML <meta> .

public:
 virtual property bool SupportsCacheControlMetaTag { bool get(); };
public virtual bool SupportsCacheControlMetaTag { get; }
member this.SupportsCacheControlMetaTag : bool
Public Overridable ReadOnly Property SupportsCacheControlMetaTag As Boolean

Nilai Properti

Boolean

true jika browser mendukung cache-control nilai untuk http-equiv atribut elemen HTML <meta> ; jika tidak, false. Defaultnya adalah true.

Contoh

Contoh kode berikut menunjukkan cara menentukan apakah browser mendukung cache-control nilai untuk http-equiv atribut elemen HTML <meta> .

<%@ 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).SupportsCacheControlMetaTag)
        {
            labelText = "Browser supports the CACHE-CONTROL value for the HTTP-EQUIV attribute of HTML META elements.";
        }
        else
        {
            labelText = "Browser does not support the CACHE-CONTROL value for the HTTP-EQUIV attribute of HTML META elements.";
        }

        Label1.Text = labelText;
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<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="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)).SupportsCacheControlMetaTag Then
            labelText = "Browser supports the CACHE-CONTROL value for the HTTP-EQUIV attribute of HTML META elements."
        Else
            labelText = "Browser does not support the CACHE-CONTROL value for the HTTP-EQUIV attribute of HTML META elements."
        End If

        Label1.Text = labelText

    End Function 'CheckBrowserCaps
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<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>

Keterangan

Nilai cache-control untuk http-equiv atribut elemen HTML <meta> memungkinkan kontrol atas penembolokan klien konten yang diunduh, yang mencakup halaman Web. Fragmen HTML berikut menunjukkan contoh:

<META HTTP-EQUIV="CACHE-CONTROL" CONTENT="NO-CACHE"/>

Jika true, penyertaan tag ini dalam <head> elemen halaman Web harus memaksa browser untuk memuat ulang konten dari server.

Jika false, adaptor kontrol server menambahkan string kueri default (__ufps=``uniquefilepathsuffix) ke nilai URL tautan yang belum memilikinya. Ini memaksa browser untuk memuat ulang konten dari server.

Properti SupportsCacheControlMetaTag juga berlaku untuk formulir header HTTP yang setara:

CACHE-CONTROL: NO-CACHE

Berlaku untuk