我写的登录的用户组件在输入用户名和密码后点击登陆的imagebutton按钮没有反应.在局域网下没有问题,上传到网站空间后就出现上面的情况.将imagebutton换成button也有同样现象,但换成linkbutton就可以.请大家帮帮我.谢谢了.代码如下: 
<%@ Control Language="c#" AutoEventWireup="false" Codebehind="userlogin.ascx.cs" Inherits="moliksys.usermodules.userlogin" TargetSchema="http://schemas.microsoft.com/intellisense/ie5"%> 
<TABLE id="Table2" cellSpacing="0" cellPadding="0" width="90%" border="0"> 
   <TR> 
      <td colSpan="3"><FONT face="宋体">   </FONT> 
      </td> 
   </TR> 
   <TR> 
      <TD style="WIDTH: 16px" align="right"><asp:image id="Image1" runat="server" ImageUrl="../images/obj_frame_top1.gif"></asp:image><asp:image id="Image5" runat="server" ImageUrl="../images/obj_frame_top2.gif"></asp:image></TD> 
      <TD background="images/obj_frame_top2.gif"><asp:image id="Image4" runat="server" ImageUrl="../images/obj_frame_top.gif"></asp:image></TD> 
      <TD width="2"><FONT face="宋体"><asp:image id="Image2" runat="server" ImageUrl="../images/obj_frame_top3.gif"></asp:image></FONT></TD> 
   </TR> 
   <TR> 
      <TD style="WIDTH: 16px; HEIGHT: 19px" align="right" bgColor="#6699ff"><asp:image id="Image3" runat="server" ImageUrl="../images/p_point02.gif"></asp:image><asp:image id="Image9" runat="server" ImageUrl="../images/p_point02.gif"></asp:image></TD> 
      <TD style="HEIGHT: 19px" bgColor="#6699ff"> 
         <TABLE id="Table1" cellSpacing="0" cellPadding="0" width="100%" bgColor="#6699ff" border="0" 
            runat="server"> 
            <TR> 
               <td colSpan="2"><FONT face="宋体"> 
                     <P align="center"> </P> 
                  </FONT> 
               </td> 
            </TR> 
            <TR> 
               <td>  
                  <asp:label id="lb_name" runat="server" ForeColor="White">用户名:</asp:label></td> 
               <td><asp:textbox id="tb_name" runat="server" Width="100px"></asp:textbox><asp:requiredfieldvalidator id="RequiredFieldValidator1" runat="server" Display="None" ControlToValidate="tb_name" 
                     ErrorMessage="请输入用户名!"></asp:requiredfieldvalidator><asp:label id="lb_nameshow" runat="server" ForeColor="White" Visible="False"></asp:label></td> 
            </TR> 
            <TR> 
               <td>  
                  <asp:label id="lb_pwd" runat="server" ForeColor="White">密码:</asp:label> 
                  <asp:LinkButton id="LinkButton2" runat="server">L</asp:LinkButton></td> 
               <td><FONT face="宋体"><asp:textbox id="tb_pwd" runat="server" Width="100px" TextMode="Password"></asp:textbox><asp:requiredfieldvalidator id="RequiredFieldValidator2" runat="server" Display="None" ControlToValidate="tb_pwd" 
                        ErrorMessage="请输入密码!"></asp:requiredfieldvalidator><asp:label id="lb_othershow" runat="server" ForeColor="White" Visible="False"></asp:label></FONT></td> 
            </TR> 
            <TR> 
               <td colSpan="2"><FONT face="宋体"> 
                     <P align="center"> </P> 
                  </FONT> 
               </td> 
            </TR> 
         </TABLE> 
         <asp:validationsummary id="ValidationSummary1" runat="server" ShowSummary="False" ShowMessageBox="True"></asp:validationsummary></TD> 
      <TD style="HEIGHT: 19px" bgColor="#6699f"></TD> 
   </TR> 
   <TR> 
      <TD style="WIDTH: 16px" bgColor="#6699ff"></TD> 
      <TD bgColor="#6699ff"><FONT face="宋体"> 
            <P align="center"><asp:imagebutton id="imgbtn_login" runat="server" ImageUrl="../images/bt2_go.gif"></asp:imagebutton>  
               <asp:hyperlink id="hl_login" runat="server" ImageUrl="../images/bt2_login.gif" Target="_blank" 
                  NavigateUrl="~/usermanage.aspx"></asp:hyperlink><BR> 
               <asp:hyperlink id="hl_edituser" runat="server" ForeColor="White" Visible="False" Font-Bold="True">[修改用户信息]</asp:hyperlink><br> 
               <asp:hyperlink id="HyperLink1" runat="server" ForeColor="White" Visible="False" NavigateUrl="~/loginoff.aspx" 
                  Font-Bold="True">[退出登录]</asp:hyperlink><br> 
               <asp:linkbutton id="LinkButton1" runat="server" ForeColor="White" Font-Bold="True" CausesValidation="False">[找回密码]</asp:linkbutton> 
            </P> 
         </FONT> 
      </TD> 
      <TD bgColor="#6699ff"></TD> 
   </TR> 
   <TR> 
      <TD style="WIDTH: 16px" align="right"><asp:image id="Image7" runat="server" ImageUrl="../images/obj_frame_bottom1.gif"></asp:image><asp:image id="Image8" runat="server" ImageUrl="../images/obj_frame_bottom2.gif"></asp:image></TD> 
      <TD background="images/obj_frame_bottom2.gif"><FONT face="宋体"></FONT></TD> 
      <TD><asp:image id="Image6" runat="server" ImageUrl="../images/obj_frame_bottom3.gif"></asp:image></TD> 
   </TR> 
   <TR> 
      <TD style="WIDTH: 16px" align="right"> </TD> 
      <TD> </TD> 
      <TD> </TD> 
   </TR> 
</TABLE> 
后台代码: 
namespace moliksys.usermodules 
{ 
   using System; 
   using System.Data; 
   using System.Drawing; 
   using System.Web; 
   using System.Web.UI.WebControls; 
   using System.Web.UI.HtmlControls; 
   using System.Data.OleDb; 
   /// <summary> 
   ///      userlogin 的摘要说明。 
   /// </summary> 
   public class userlogin : System.Web.UI.UserControl 
   { 
      protected System.Web.UI.HtmlControls.HtmlTable Table1; 
      protected System.Web.UI.HtmlControls.HtmlTableCell TD2; 
      protected System.Web.UI.WebControls.TextBox tb_name; 
      protected System.Web.UI.WebControls.TextBox tb_pwd; 
      protected System.Web.UI.WebControls.RequiredFieldValidator RequiredFieldValidator1; 
      protected System.Web.UI.WebControls.RequiredFieldValidator RequiredFieldValidator2; 
      protected System.Web.UI.WebControls.ValidationSummary ValidationSummary1; 
      private linkdatabase link=new linkdatabase(); 
      protected System.Web.UI.WebControls.Image Image1; 
      protected System.Web.UI.WebControls.Image Image2; 
      protected System.Web.UI.WebControls.Image Image3; 
      protected System.Web.UI.WebControls.Image Image4; 
      protected System.Web.UI.WebControls.Image Image5; 
      protected System.Web.UI.WebControls.Image Image6; 
      protected System.Web.UI.WebControls.Image Image7; 
      protected System.Web.UI.WebControls.Image Image8; 
      protected System.Web.UI.WebControls.Label lb_name; 
      protected System.Web.UI.WebControls.Label lb_nameshow; 
      protected System.Web.UI.WebControls.Label lb_othershow; 
      protected System.Web.UI.WebControls.Label lb_pwd; 
      protected System.Web.UI.WebControls.HyperLink hl_edituser; 
      protected System.Web.UI.WebControls.HyperLink hl_login; 
      protected System.Web.UI.WebControls.Image Image9; 
      protected System.Web.UI.WebControls.LinkButton LinkButton1; 
      protected System.Web.UI.WebControls.HyperLink HyperLink1; 
      protected System.Web.UI.WebControls.LinkButton LinkButton2; 
      protected System.Web.UI.WebControls.ImageButton imgbtn_login; 
      private DataSet ds=new DataSet(); 
      private void Page_Load(object sender, System.EventArgs e) 
      { 
         // 在此处放置用户代码以初始化页面 
          
          
            Response.Write("<script>alert('"+Session["loginflag"].ToString()+"')</script>"); 
            if((bool)Session["loginflag"]==true) 
            { 
               this.tb_name.Visible=false; 
               this.tb_pwd.Visible=false; 
               this.imgbtn_login.Visible=false; 
               this.hl_login.Visible=false; 
               this.lb_nameshow.Visible=true; 
               this.lb_nameshow.Text=Session["username"].ToString(); 
               this.lb_pwd.Text="用户角色:"; 
               this.lb_othershow.Visible=true; 
               this.lb_othershow.Text=Session["rolename"].ToString(); 
               this.hl_edituser.Visible=true; 
               this.hl_edituser.NavigateUrl="usermanage.aspx?userid="+Session["userid"].ToString(); 
               this.HyperLink1.Visible=true; 
               this.LinkButton1.Visible=false; 
            } 
          
      } 
      #region Web 窗体设计器生成的代码 
      override protected void OnInit(EventArgs e) 
      { 
         // 
         // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。 
         // 
         InitializeComponent(); 
         base.OnInit(e); 
      } 
       
      /// <summary> 
      ///      设计器支持所需的方法 - 不要使用代码编辑器 
      ///      修改此方法的内容。 
      /// </summary> 
      private void InitializeComponent() 
      { 
         this.LinkButton2.Click += new System.EventHandler(this.LinkButton2_Click); 
         this.LinkButton1.Click += new System.EventHandler(this.LinkButton1_Click); 
         this.Load += new System.EventHandler(this.Page_Load); 
      } 
      #endregion 
      private void imgbtn_login_Click(object sender, System.Web.UI.ImageClickEventArgs e) 
      { 
         string checkstr="SELECT 角色表.角色编号, 角色表.角色名称, 角色表.角色权限, 用户表.用户编号, 用户表.用户名称, 用户表.密码, 用户表.电子邮箱, 用户表.所属角色编号, 用户表.真实姓名, 用户表.地址, 用户表.电话, 用户表.移动电话, 用户表.密码问题, 用户表.问题答案, 用户表.用户建立时间, 用户表.上一次登录时间, 用户表.更新时间, 用户表.访问次数, 用户表.头像编号, 用户表.用户权限, 用户表.性别 FROM 角色表 INNER JOIN 用户表 ON 角色表.角色编号 = 用户表.所属角色编号  where 用户名称='"+clearstring.inputtext(this.tb_name.Text.Trim(),this.tb_name.Text.Length)+"' and 密码='"+clearstring.inputtext(this.tb_pwd.Text.Trim(),this.tb_pwd.Text.Length)+"'"; 
         string checktb="临时表"; 
          
         ds=this.link.selectdatabase(checkstr,checktb); 
          
         if (ds.Tables[0].Rows.Count>0) 
         { 
             
            Session["username"]=ds.Tables["临时表"].Rows[0]["用户名称"].ToString(); 
            Session["userid"]=ds.Tables["临时表"].Rows[0]["用户编号"].ToString(); 
            Session["realname"]=ds.Tables["临时表"].Rows[0]["真实姓名"].ToString(); 
            Session["permiss"]=ds.Tables["临时表"].Rows[0]["用户权限"].ToString(); 
            Session["rolename"]=ds.Tables["临时表"].Rows[0]["角色名称"].ToString(); 
            Session["roleid"]=ds.Tables["临时表"].Rows[0]["角色编号"].ToString(); 
            Session["loginflag"]=true; 
            Response.Redirect("index.aspx"); 
         } 
         else 
         { 
            this.tb_name.Text=""; 
            this.tb_pwd.Text=""; 
            Response.Write("<script>alert('你的用户名或密码有误,请重新输入!')</script>"); 
         } 
      } 
      private void LinkButton1_Click(object sender, System.EventArgs e) 
      { 
         Response.Write("<script>window.open('forgotpwd.aspx','newwin','width=500,height=300');</script>"); 
         Response.Write("<script>window.focus();</script>"); 
      } 
      private void LinkButton2_Click(object sender, System.EventArgs e) 
      { 
         string checkstr="SELECT 角色表.角色编号, 角色表.角色名称, 角色表.角色权限, 用户表.用户编号, 用户表.用户名称, 用户表.密码, 用户表.电子邮箱, 用户表.所属角色编号, 用户表.真实姓名, 用户表.地址, 用户表.电话, 用户表.移动电话, 用户表.密码问题, 用户表.问题答案, 用户表.用户建立时间, 用户表.上一次登录时间, 用户表.更新时间, 用户表.访问次数, 用户表.头像编号, 用户表.用户权限, 用户表.性别 FROM 角色表 INNER JOIN 用户表 ON 角色表.角色编号 = 用户表.所属角色编号  where 用户名称='"+clearstring.inputtext(this.tb_name.Text.Trim(),this.tb_name.Text.Length)+"' and 密码='"+clearstring.inputtext(this.tb_pwd.Text.Trim(),this.tb_pwd.Text.Length)+"'"; 
         string checktb="临时表"; 
          
         ds=this.link.selectdatabase(checkstr,checktb); 
          
         if (ds.Tables[0].Rows.Count>0) 
         { 
             
            Session["username"]=ds.Tables["临时表"].Rows[0]["用户名称"].ToString(); 
            Session["userid"]=ds.Tables["临时表"].Rows[0]["用户编号"].ToString(); 
            Session["realname"]=ds.Tables["临时表"].Rows[0]["真实姓名"].ToString(); 
            Session["permiss"]=ds.Tables["临时表"].Rows[0]["用户权限"].ToString(); 
            Session["rolename"]=ds.Tables["临时表"].Rows[0]["角色名称"].ToString(); 
            Session["roleid"]=ds.Tables["临时表"].Rows[0]["角色编号"].ToString(); 
            Session["loginflag"]=true; 
            Response.Redirect("index.aspx"); 
         } 
         else 
         { 
            this.tb_name.Text=""; 
            this.tb_pwd.Text=""; 
            Response.Write("<script>alert('你的用户名或密码有误,请重新输入!')</script>"); 
         } 
      } 
                         
   } 
} 

 
											





 
	    