ViewStateException.UserAgent 属性

定义

命名空间:

System.Web.UI

程序集:

System.Web.dll

获取导致视图状态异常的 HTTP 请求的浏览器类型。

public:
 property System::String ^ UserAgent { System::String ^ get(); };

public string UserAgent { get; }

member this.UserAgent : string

Public ReadOnly Property UserAgent As String

属性值

String

一个 String，其中包含用户代理（通常为浏览器类型）。

示例

下面的代码示例演示如何实现一个方法，该方法反序列化 base64 编码的字符串并返回 ICollection 属性设置的集合。 方法 Deserialize 可以引发一个 HttpException 异常，该异常将 ViewStateException 对象作为内部异常。 该示例演示如何捕获 HttpException 异常并从 对象检索属性 ViewStateException 。

private ICollection LoadControlProperties(string serializedProperties)
{

    ICollection controlProperties = null;

    // Create an ObjectStateFormatter to deserialize the properties.
    ObjectStateFormatter formatter = new ObjectStateFormatter();

    try
    {
        // Call the Deserialize method.
        controlProperties = (ArrayList)formatter.Deserialize(serializedProperties);
    }
    catch (HttpException e)
    {
        ViewStateException vse = (ViewStateException)e.InnerException;
        String logMessage;

        logMessage = "ViewStateException. Path: " + vse.Path + Environment.NewLine;
        logMessage += "PersistedState: " + vse.PersistedState + Environment.NewLine;
        logMessage += "Referer: " + vse.Referer + Environment.NewLine;
        logMessage += "UserAgent: " + vse.UserAgent + Environment.NewLine;

        LogEvent(logMessage);

        if (vse.IsConnected)
        {
            HttpContext.Current.Response.Redirect("ErrorPage.aspx");
        }
        else
        {
            throw e;
        }
    }
    return controlProperties;
}

Private Function LoadControlProperties(ByVal serializedProperties As String) As ICollection

    Dim controlProperties As ICollection = Nothing

    ' Create an ObjectStateFormatter to deserialize the properties.
    Dim formatter As New ObjectStateFormatter()

    Try
        ' Call the Deserialize method.
        controlProperties = CType(formatter.Deserialize(serializedProperties), ArrayList)
    Catch e As HttpException
        Dim vse As ViewStateException
        Dim logMessage As String

        vse = e.InnerException

        logMessage = "ViewStateException. Path: " + vse.Path + Environment.NewLine
        logMessage += "PersistedState: " + vse.PersistedState + Environment.NewLine
        logMessage += "Referer: " + vse.Referer + Environment.NewLine
        logMessage += "UserAgent: " + vse.UserAgent + Environment.NewLine

        LogEvent(logMessage)

        If (vse.IsConnected) Then
            HttpContext.Current.Response.Redirect("ErrorPage.aspx")
        Else
            Throw e
        End If
    End Try
    Return controlProperties
End Function 'LoadControlProperties

注解

此属性返回与 属性中的 HTTP_USER_AGENTServerVariables 变量相同的值。