error CS0246: 找不到类型或命名空间名称“UserManager”(是否缺少 using 指令或程序集引用?)

[y13550297325]

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using BLL;
using Model;

public partial class admin_AdminLogin : System.Web.UI.Page
{
protected UserManager userbll = new UserManager();
protected void Page_Load(object sender, EventArgs e)
{

}
protected void imgb_Sure_Click(object sender, ImageClickEventArgs e)
{
if(userbll.GetModel(this.txtLoginId.ToString(),this.txtLoginPwd.ToString())){
Response.Redirect("~/Admin/ListAllUsers.aspx");
}
}
protected void imgb_Cancel_Click(object sender, ImageClickEventArgs e)
{
this.txtLoginId.Text = string.Empty;
this.txtLoginPwd.Text = string.Empty;
}
}

[Im_Sorry]

提示很明显，。引用一下，添加引用就好了！

[y13550297325]

我 已经 添加引用啦

[y13550297325]