谁知道怎么防止下拉菜单等按钮冲刷密码的值！

ksni56z - 2008-7-24 9:11:00

就是我在先前在文本框写上密码后在下面用下拉菜单的时候会把先前写的密码给冲刷掉听朋友说可以用内嵌解决但是那样太麻烦有不有其他办法可以解决啊

suresy - 2008-7-24 9:40:00

密码一般会在回发之后由系统自动清空，是因为考虑到安全问题。你的下拉菜单可能开启了AutoPostBack，所以每选一项就会回发一次使密码被清空。把下拉菜单的AutoPostBack属性禁用就可以了，如果下拉菜单确实需要AutoPostBack，就只能用内嵌防止页面刷新了

suresy - 2008-7-24 10:01:00

我刚才试了一下，下拉菜单需要AutoPostBack的话除了内嵌还可以使用客户端JavaScript自己重新填充，不过这样就会把密码暴露在页面的源文件，造成安全问题。你参考一下吧。

在下拉菜单的SelectedIndexChanged事件中执行如下代码：
string script = "<script>document.getElementById('TextBox1').value = '" + TextBox1.Text + "';</script>";
Page.RegisterStartupScript("", script);

注意输出脚本要使用Page.RegisterStartupScript
使用Response.Write的话密码还是会被清空的

ksni56z - 2008-7-24 15:16:00

是加在下拉菜单下吗我加了但还是会清空也。

suresy - 2008-7-24 16:11:00

不大清楚你是什么情况，要不你把源代码贴上来吧

ksni56z - 2008-7-24 17:22:00

好的
这是我的源码了不知道怎么回事现在老出现未实例化对象

public class reg : System.Web.UI.Page
{
protected System.Web.UI.WebControls.CheckBox CheckBox1;
protected System.Web.UI.WebControls.Button Button1;
protected System.Web.UI.WebControls.RadioButtonList RadioButtonList1;
protected System.Web.UI.WebControls.Image Image1;
protected System.Web.UI.HtmlControls.HtmlTable Table4;
protected System.Web.UI.WebControls.ImageButton ImageButton2;
protected System.Web.UI.WebControls.TextBox usernametb;
protected System.Web.UI.WebControls.TextBox passtb;
protected System.Web.UI.WebControls.TextBox repasstb;
protected System.Web.UI.WebControls.TextBox emailtb;
protected System.Web.UI.WebControls.DropDownList ddl1;
protected System.Web.UI.WebControls.TextBox resulttb;
protected System.Web.UI.WebControls.DropDownList ddl2;
protected System.Web.UI.WebControls.TextBox qmtb;
protected System.Web.UI.WebControls.TextBox yzmtb;
protected System.Web.UI.HtmlControls.HtmlInputFile F;
protected System.Web.UI.WebControls.TextBox fromtb;
protected System.Web.UI.WebControls.RequiredFieldValidator RequiredFieldValidator1;
protected System.Web.UI.WebControls.RequiredFieldValidator RequiredFieldValidator2;
protected System.Web.UI.WebControls.RequiredFieldValidator RequiredFieldValidator3;
protected System.Web.UI.WebControls.RequiredFieldValidator RequiredFieldValidator4;
protected System.Web.UI.WebControls.CompareValidator CompareValidator1;
protected System.Web.UI.WebControls.RegularExpressionValidator RegularExpressionValidator1;
protected System.Web.UI.WebControls.Label Label1;
protected System.Web.UI.WebControls.ImageButton ImageButton1;

private void Page_Load(object sender, System.EventArgs e)
{
if(CheckBox1.Checked)
{
Table4.Visible=true;
}
else
{
Table4.Visible=false;
}
if(IsPostBack)
return;
Image1.ImageUrl="face/"+".gif";
bind2();
Table4.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.ddl1.SelectedIndexChanged += new System.EventHandler(this.ddl1_SelectedIndexChanged);
this.ddl2.SelectedIndexChanged += new System.EventHandler(this.ddl2_SelectedIndexChanged);
this.Button1.Click += new System.EventHandler(this.Button1_Click);
this.Load += new System.EventHandler(this.Page_Load);

}
#endregion
public string filename;

void bind2()
{
ddl2.DataTextField="face";
ddl2.DataValueField="face";

SqlConnection conn=new SqlConnection(ConfigurationSettings.AppSettings["str"]);
string sql="select * from bbs_face";
SqlCommand cmd=new SqlCommand(sql,conn);
conn.Open();
ddl2.DataSource=cmd.ExecuteReader();
ddl2.DataBind();
conn.Close();
}
private void Button1_Click(object sender, System.EventArgs e)
{
string mm2=Convert.ToString(passtb.Text);
string xm=usernametb.Text;
string mm=FormsAuthentication.HashPasswordForStoringInConfigFile(passtb.Text,"sha1");
string yx=emailtb.Text;
string wt=ddl1.SelectedItem.Value;
string da=resulttb.Text;
string xb=RadioButtonList1.SelectedItem.Value;
string lz=fromtb.Text;
string qm=qmtb.Text;
string face=ddl2.SelectedItem.Value;
string yzm=yzmtb.Text;

// try
// {
//
if(mm2.Length<6)
{
RegisterStartupScript("","<script>alert('密码不得少于6位数！')</script>");
}
else
{
if(yzm==Session["CheckCode"].ToString())
{

HttpPostedFile hpf=F.PostedFile;
int cl=hpf.FileName.Length;

if(cl>0)
{
if(hpf.FileName=="")
{

RegisterStartupScript("","<script>alert('你上传的文件不能为空！')</script>");

}
else
{
string kuo=Path.GetExtension(hpf.FileName).ToLower();
if(kuo==".jpg" || kuo==".gif" || kuo==".bmp" )
{

if(hpf.ContentLength<660000)
{
filename=DateTime.Now.ToString("yyyMMdd")+Path.GetFileName(hpf.FileName);
string filepath=Server.MapPath("loadfile/");
hpf.SaveAs(filepath+filename);

}
else
{
RegisterStartupScript("","<script>alert('请将你所上传的文件控制在600kb内！')</script>");
}
}
else
{
RegisterStartupScript("","<script>alert('上传图片的格式要为jpg,gif,bmp！')</script>");
}
}
}
else
{
filename=face;
}

conndb cdb=new conndb();
int i=cdb.reg(xm,mm,filename,xb,qm,yx,wt,da,lz);
FormsAuthentication.SetAuthCookie(i.ToString(),false);
string a=Request["ReturnUrl"];

JScript.Redirect("cg.aspx?d=a");
}
else
{
Label1.Text="请正确输入验证码,如果看不清请点击刷新!";
}

}

// }
// catch
// {
// RegisterStartupScript("","<script>alert('该用户已经被注册,请重新输入！')</script>");
// }
//

}

private void ddl2_SelectedIndexChanged(object sender, System.EventArgs e)
{
string face=ddl2.SelectedItem.Value;
Image1.ImageUrl="face/"+face;
}

private void ddl1_SelectedIndexChanged(object sender, System.EventArgs e)
{
string script = "<script>document.getElementById('passtb').value = '" + passtb.Text + "';</script>";
Page.RegisterStartupScript("", script);

}

}
}

suresy - 2008-7-24 17:31:00

还有aspx页面的源代码呢？少了那个也没办法调试喔......

ksni56z - 2008-7-24 17:35:00

我上面的是aspx源码啊你说的是html代码吗

<%@ Register TagPrefix="uc1" TagName="head" Src="head.ascx" %>
<%@ Page language="c#" Codebehind="reg.aspx.cs" AutoEventWireup="false" Inherits="BBS.reg" validateRequest=false %>
<%@ Register TagPrefix="uc1" TagName="foot" Src="foot.ascx" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
<HEAD>
<title>reg</title>
<meta content="Microsoft Visual Studio .NET 7.1" name="GENERATOR">
<meta content="C#" name="CODE_LANGUAGE">
<meta content="JavaScript" name="vs_defaultClientScript">
<meta content="http://schemas.microsoft.com/intellisense/ie5" name="vs_targetSchema">
</HEAD>
<body bottomMargin="0" leftMargin="0" topMargin="0">
<form id="Form1" method="post" runat="server">
<P align="center"><uc1:head id="Head1" runat="server"></uc1:head><FONT face="宋体"><BR>
</FONT><FONT face="宋体"></FONT><FONT face="宋体">
<TABLE id="Table1" cellSpacing="0" cellPadding="0" width="760" border="0">
<TR>
<TD style="WIDTH: 24px"><asp:imagebutton id="ImageButton1" runat="server" ImageUrl="pic/s.gif"></asp:imagebutton></TD>
<TD><FONT color="#2b76b0"><FONT size="2">口袋吧</FONT> » </FONT><FONT color="#000000"><FONT size="2">
注册</FONT></FONT></TD>
</TR>
</TABLE>
<BR>
<TABLE id="Table2" cellSpacing="1" cellPadding="0" width="760" bgColor="#7692b7" border="0">
<TR bgColor="#ffffff">
<TD vAlign="middle">
<TABLE id="Table3" cellSpacing="1" cellPadding="0" width="99%" align="center" bgColor="#7692b7"
border="0">
<TR>
<TD style="HEIGHT: 25px" align="center" bgColor="#e8f3fd" colSpan="2">
<P align="left"><FONT color="#666666" size="2"> 基本信息(*为必填)</FONT></P>
</TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 229px">
<P align="left"><FONT size="2"> 用户名<FONT color="#ff0000">*</FONT><BR>
不能有空格，可以是中文</FONT></P>
</TD>
<TD align="center">
<P align="left"><asp:textbox id="usernametb" runat="server" Width="160px"></asp:textbox>
<asp:RequiredFieldValidator id="RequiredFieldValidator1" runat="server" Font-Size="12px" ErrorMessage="用户名不能缺省！"
ControlToValidate="usernametb"></asp:RequiredFieldValidator></P>
</TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 229px">
<P align="left"><FONT size="2"> 密    码<FONT color="#ff0000">*</FONT><BR>
允许英文字母或数字，长度最小值6</FONT></P>
</TD>
<TD align="center">
<P align="left"><asp:textbox id="passtb" runat="server" Width="160px" TextMode="Password"></asp:textbox>
<asp:RequiredFieldValidator id="RequiredFieldValidator2" runat="server" Font-Size="12px" ErrorMessage="密码不能缺省！"
ControlToValidate="passtb"></asp:RequiredFieldValidator></P>
</TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 229px">
<P align="left"><FONT size="2"> 重复密码</FONT><FONT color="#ff0000" size="3">*</FONT></P>
</TD>
<TD align="center">
<P align="left"><asp:textbox id="repasstb" runat="server" Width="160px" TextMode="Password"></asp:textbox>
<asp:RequiredFieldValidator id="RequiredFieldValidator3" runat="server" Font-Size="12px" ErrorMessage="重复密码不能缺省！"
ControlToValidate="repasstb">*</asp:RequiredFieldValidator>
<asp:CompareValidator id="CompareValidator1" runat="server" Font-Size="12px" ForeColor="Blue" ErrorMessage="两次密码输入不一致！"
ControlToValidate="repasstb" ControlToCompare="passtb"></asp:CompareValidator></P>
</TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 229px">
<P align="left"><FONT size="2">  E_mial</FONT><FONT color="#ff0000" size="3">*</FONT></P>
</TD>
<TD align="center">
<P align="left"><asp:textbox id="emailtb" runat="server" Width="160px" Font-Size="12px"></asp:textbox>
<asp:RequiredFieldValidator id="RequiredFieldValidator4" runat="server" Font-Size="12px" ErrorMessage="邮箱不能缺省！"
ControlToValidate="emailtb">*</asp:RequiredFieldValidator>
<asp:RegularExpressionValidator id="RegularExpressionValidator1" runat="server" Font-Size="12px" ErrorMessage="请输入正确的邮箱格式！"
ControlToValidate="emailtb" ValidationExpression="\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*"></asp:RegularExpressionValidator></P>
</TD>
</TR>
<TR bgColor="#e8f3fd">
<TD colSpan="2">
<P align="left"><FONT size="2"> 高级选项</FONT>
<asp:checkbox id="CheckBox1" runat="server" Font-Size="12px" Text="显示高级用户选项" AutoPostBack="True"></asp:checkbox></P>
</TD>
</TR>
<TR bgColor="#ffffff">
<TD colSpan="2">
<TABLE id="Table4" cellSpacing="1" cellPadding="0" width="100%" border="0" bgColor="#7692b7"
runat="server">
<TR bgColor="#ffffff">
<TD style="WIDTH: 206px; HEIGHT: 17px"><FONT size="2"> 安全保护(用于忘记了密码找回!)</FONT></TD>
<TD style="HEIGHT: 17px">
<asp:DropDownList id="ddl1" runat="server">
<asp:ListItem Selected="True">无安全提问</asp:ListItem>
<asp:ListItem Value="你上小学的名字">你上小学的名字</asp:ListItem>
<asp:ListItem Value="你母亲的名字">你母亲的名字</asp:ListItem>
<asp:ListItem Value="你最喜欢的动物">你最喜欢的动物</asp:ListItem>
<asp:ListItem Value="你最喜欢听的歌">你最喜欢听的歌</asp:ListItem>
<asp:ListItem Value="你最爱的人是谁">你最爱的人是谁</asp:ListItem>
<asp:ListItem Value="你的学生证号是多少">你的学生证号是多少</asp:ListItem>
</asp:DropDownList></TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 206px">
<P align="center"> <FONT size="2">回    答</FONT></P>
</TD>
<TD>
<asp:TextBox id="resulttb" runat="server"></asp:TextBox></TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 206px; HEIGHT: 47px">
<P align="center"> <FONT size="2">性    别</FONT></P>
</TD>
<TD style="HEIGHT: 47px">
<asp:RadioButtonList id="RadioButtonList1" runat="server" Font-Size="12px" RepeatDirection="Horizontal"
Width="69px">
<asp:ListItem Value="<img src=pic/male.gif>" Selected="True"><img src=pic/male.gif></asp:ListItem>
<asp:ListItem Value="<img src=pic/female.gif>"><img src=pic/female.gif></asp:ListItem>
</asp:RadioButtonList></TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 206px">
<P align="center"> <FONT size="2">来    自</FONT></P>
</TD>
<TD>
<asp:TextBox id="fromtb" runat="server"></asp:TextBox></TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 206px; HEIGHT: 5px">
<P align="center"> <FONT size="2">头像选择</FONT></P>
</TD>
<TD style="HEIGHT: 5px" vAlign="top">
<asp:DropDownList id="ddl2" runat="server" Width="95px" AutoPostBack="True"></asp:DropDownList>
<asp:Image id="Image1" runat="server" Height="50px" Width="50px"></asp:Image></TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 206px">
<P align="center"> <FONT size="2">自定义头像</FONT></P>
</TD>
<TD><INPUT type="file" id="F" name="File1" runat="server"></TD>
</TR>
<TR bgColor="#ffffff">
<TD style="WIDTH: 206px">
<P align="center"> <FONT size="2">个性签名</FONT></P>
</TD>
<TD>
<asp:TextBox id="qmtb" runat="server" Width="401px" TextMode="MultiLine"></asp:TextBox></TD>
</TR>
</TABLE>
</TD>
</TR>
<TR bgColor="#ffffff">
<TD colSpan="2">
<P align="left"><FONT size="2"> 认证码 <FONT color="#ff0000">*</FONT></FONT>
<asp:TextBox id="yzmtb" runat="server"></asp:TextBox>
<asp:ImageButton id="ImageButton2" runat="server" ImageUrl="Code.aspx"></asp:ImageButton>
<asp:Label id="Label1" runat="server" Font-Size="12px" ForeColor="Red"></asp:Label></P>
</TD>
</TR>
<TR bgColor="#ffffff">
<TD align="center" colSpan="2">
<asp:Button id="Button1" runat="server" Font-Size="12px" Height="20px" Width="49px" Text="提交"
ForeColor="#005368" BorderColor="Black" BorderStyle="Solid" BorderWidth="1px" BackColor="#C9E8EC"></asp:Button></TD>
</TR>
</TABLE>
</TD>
</TR>
</TABLE>
<BR>
<uc1:foot id="Foot1" runat="server"></uc1:foot></FONT></P>
</form>
</body>
</HTML>

ksni56z - 2008-7-24 17:38:00

把整个reg传上来行吗

附件: reg.rar

suresy - 2008-7-24 20:09:00

抱歉，今天比较忙，没办法帮你详细调试了，我大概看了一下代码，问题有可能出在这里：
<asp:DropDownList id="ddl2" runat="server" Width="95px" AutoPostBack="True"></asp:DropDownList>

这个下拉菜单开启了自动回发，所以应该在相应的事件中输出填充脚本：
private void ddl2_SelectedIndexChanged(object sender, System.EventArgs e)
{
//其它代码......
string script = "<script>document.getElementById('passtb').value = '" + passtb.Text + "';</script>";
Page.RegisterStartupScript("", script);
}

下拉菜单ddl1没有开启自动回发，不需要输出填充脚本

另外，如果你想每次回发都自动填充密码，而不想每个控件事件都加入上述代码的话，可以在Page_Load事件中：
if(IsPostBack)
{
string script = "<script>document.getElementById('passtb').value = '" + passtb.Text + "';</script>";
Page.RegisterStartupScript("", script);
}

ksni56z - 2008-7-25 0:03:00

恩先谢谢你那我在试试看把

zorosuteng - 2008-7-25 9:20:00

用 Ajax 控件之 UpdatePanel 实现局部刷新就能解决你的问题。简单易用。和其他控件一样拖拽使用就行了。

ksni56z - 2008-7-26 19:39:00

Ajax 控件之 UpdatePanel 这个贴吧里有下载地址吗我找了好多地方都找到下载的啊

zorosuteng - 2008-7-28 10:39:00

http://www.codeplex.com/AjaxControlToolkit/Release/ProjectReleases.aspx?ReleaseId=11121 这是地址，下载编译后引用dll文件即可。

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