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HttpCapabilitiesBase.SupportsUncheck Property

  • Reference

Definition

Namespace:
System.Web.Configuration
Assembly:
System.Web.dll

Gets a value indicating whether the clearing of a checked HTML <input type=checkbox> element is reflected in postback data.

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

Property Value

Boolean

true if the clearing of a checked HTML <input type=checkbox> element is reflected in postback data; otherwise, false. The default is true.

Examples

The following code example shows how to determine whether the clearing of a checked HTML <input type=checkbox> element is reflected in postback data.

<%@ 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).SupportsUncheck)
        {
            labelText = "Browser reflects the unchecking of a checked HTML CHECKBOX element in postback data.";
        }
        else
        {
            labelText = "Browser does not reflect the unchecking of a checked HTML CHECKBOX element in postback data.";
        }

        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)).SupportsUncheck Then
            labelText = "Browser reflects the unchecking of a checked HTML CHECKBOX element in postback data."
        Else
            labelText = "Browser does not reflect the unchecking of a checked HTML CHECKBOX element in postback data."
        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>

Remarks

If false, the value of the checked attribute of HTML <input type=checkbox> elements is omitted from postback data.

Applies to