HttpParseException 类
发生分析错误时引发的异常。
**命名空间:**System.Web
**程序集:**System.Web（在 system.web.dll 中）
语法
声明
<SerializableAttribute> _
Public NotInheritable Class HttpParseException
Inherits HttpException
用法
Dim instance As HttpParseException
[SerializableAttribute]
public sealed class HttpParseException : HttpException
[SerializableAttribute]
public ref class HttpParseException sealed : public HttpException
/** @attribute SerializableAttribute() */
public final class HttpParseException extends HttpException
SerializableAttribute
public final class HttpParseException extends HttpException
备注
HttpParseException 类是一个特定于 HTTP 的异常类，ASP.NET 可通过该类输出分析器异常信息。有关引发和处理异常的更多信息，请参见 处理和引发异常。
示例
下面的示例演示如何使用 HttpParseException 来自定义在页分析期间生成的错误。此示例中定义了一个自定义的 HtmlSelect 控件。如果自定义控件的子元素不属于指定的类型，则在自定义 HtmlSelectBuilder 的 GetChildControlType 重写方法中将引发一个 HttpParseException。若要生成一个分析异常，请将子元素文本 MyCustomOption 更改为其他任何字符串。
<%@ Page Language="VB"%>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB" Assembly="Samples.AspNet.VB" %>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>HttpParseException Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>HttpParseException Example</h3>
<aspSample:CustomHtmlSelectWithHttpParseException
id="customhtmlselect1"
runat="server">
<aspSample:MyCustomOption optionid="option1" value="1"/>
<aspSample:MyCustomOption optionid="option2" value="2"/>
<aspSample:MyCustomOption optionid="option3" value="3"/>
</aspSample:CustomHtmlSelectWithHttpParseException>
</form>
</body>
</html>
<%@ Page Language="C#"%>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS" Assembly="Samples.AspNet.CS" %>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>HttpParseException Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>HttpParseException Example</h3>
<aspSample:CustomHtmlSelectWithHttpParseException
id="customhtmlselect1"
runat="server">
<aspSample:MyCustomOption optionid="option1" value="1"/>
<aspSample:MyCustomOption optionid="option2" value="2"/>
<aspSample:MyCustomOption optionid="option3" value="3"/>
</aspSample:CustomHtmlSelectWithHttpParseException>
</form>
</body>
</html>
Imports System
Imports System.Security.Permissions
Imports System.Collections
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.HtmlControls
Namespace Samples.AspNet.VB
' Define a child control for the custom HtmlSelect.
Public Class MyCustomOption
Private _id As String
Private _value As String
Public Property optionid() As String
Get
Return _id
End Get
Set(ByVal value As String)
_id = value
End Set
End Property
Public Property value() As String
Get
Return _value
End Get
Set(ByVal value As String)
_value = value
End Set
End Property
End Class
' Define a custom HtmlSelectBuilder.
Public Class MyHtmlSelectBuilderWithparseException
Inherits HtmlSelectBuilder
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public Overrides Function GetChildControlType(ByVal tagName As String, ByVal attribs As IDictionary) As Type
' Distinguish between two possible types of child controls.
If tagName.ToLower().EndsWith("mycustomoption") Then
Return GetType(MyCustomOption)
Else
Throw New HttpParseException("This custom HtmlSelect control" & _
"requires child elements of the form ""MyCustomOption""")
End If
End Function
End Class
<ControlBuilderAttribute(GetType(MyHtmlSelectBuilderWithparseException))> _
Public Class CustomHtmlSelectWithHttpParseException
Inherits HtmlSelect
' Override the AddParsedSubObject method.
Protected Overrides Sub AddParsedSubObject(ByVal obj As Object)
Dim _outputtext As String
If TypeOf obj Is MyCustomOption Then
_outputtext = "custom select option : " + CType(obj, MyCustomOption).value
Dim li As New ListItem(_outputtext, CType(obj, MyCustomOption).value)
MyBase.Items.Add(li)
End If
End Sub
End Class
End Namespace
using System;
using System.Security.Permissions;
using System.Collections;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
namespace Samples.AspNet.CS
{
// Define a child control for the custom HtmlSelect.
public class MyCustomOption
{
string _id;
string _value;
public string optionid
{
get
{ return _id; }
set
{ _id = value; }
}
public string value
{
get
{ return _value; }
set
{ _value = value; }
}
}
// Define a custom HtmlSelectBuilder.
public class MyHtmlSelectBuilderWithparseException : HtmlSelectBuilder
{
[AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
public override Type GetChildControlType(string tagName, IDictionary attribs)
{
// Distinguish between two possible types of child controls.
if (tagName.ToLower().EndsWith("mycustomoption"))
{
return typeof(MyCustomOption);
}
else
{
throw new HttpParseException("This custom HtmlSelect control" + "requires child elements of the form \"MyCustomOption\"");
}
}
}
[ControlBuilderAttribute(typeof(MyHtmlSelectBuilderWithparseException))]
public class CustomHtmlSelectWithHttpParseException : HtmlSelect
{
// Override the AddParsedSubObject method.
protected override void AddParsedSubObject(object obj)
{
string _outputtext;
if (obj is MyCustomOption)
{
_outputtext = "custom select option : " + ((MyCustomOption)obj).value;
ListItem li = new ListItem(_outputtext, ((MyCustomOption)obj).value);
base.Items.Add(li);
}
}
}
}
.NET Framework 安全性
- AspNetHostingPermission 用于在宿主环境中进行操作。要求值：LinkDemand；权限值：Minimal。
继承层次结构
System.Object
System.Exception
System.SystemException
System.Runtime.InteropServices.ExternalException
System.Web.HttpException
System.Web.HttpParseException
线程安全
此类型的任何公共静态（Visual Basic 中的 Shared）成员都是线程安全的，但不保证所有实例成员都是线程安全的。
平台
Windows 98、Windows 2000 SP4、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。
版本信息
.NET Framework
受以下版本支持：2.0、1.1、1.0
请参见
参考
HttpParseException 成员
System.Web 命名空间
HtmlSelect
HtmlSelectBuilder