ASP.NET设置404页面返回302HTTP状态码的解决方法

<customErrors mode="On" defaultRedirect="404.aspx"> 
<error statusCode="403" redirect="404.aspx" /> 
<error statusCode="404" redirect="404.aspx" /> 
<error statusCode="400" redirect="404.aspx" /> 
</customErrors> 

protected void Application_Error(object sender, EventArgs e) 
{ 
//在出现未处理的错误时运行的代码 
this.FileNotFound_Error(); 
} 
/// <summary> 
/// 404错误处理 
/// </summary> 
private void FileNotFound_Error() 
{ 
HttpException erroy = Server.GetLastError() as HttpException; 
if (erroy != null && erroy.GetHttpCode() == 404) 
{ 
Server.ClearError(); 
string path = "~/404.aspx"; 
Server.Transfer(path); 
//Context.Handler = PageParser.GetCompiledPageInstance(path, Server.MapPath(path), Context); 
} 
}