在哪里摔倒
就在哪里自己爬起来
我们受够了没有？DropDownList和ListBox使用js后出错
经常都会用到这种处理方式：在弹出窗口里修改数据，把数据返回，然后呢，在当前窗口的DropDownList或者ListBox控件里添加在编写程序时是不确定的ListItem
这种方式经常用到，就像发送邮件时可以在弹出的窗口里添加附件，然后把附件的信息返回一样，从一个模态窗口返回不确定的项，要把这些项，使用js添加到<select>标签里很容易，就是如果要让这些不确定的项，通过上面的回发时的验证，好难好难。。。
添加的项，不可以通过js添加，一定要通过服务器端的代码来添加！
不要和我说有Render方法可以注册，在编写程序的时候，根本就不知道要注册的内容是什么，注册什么东西？
先记下这四个连接：
2006-11-15 14:32:00《使用showModalDialog打开模态窗口添加数据后刷新原窗口》：user1/9/archives/2006/3024.html
2006-12-28 19:13:00《模板列里出现“DropDownList 有一个无效 SelectedValue”的解决方法》：user1/9/archives/2006/3237.html
2007-01-10 19:24:00《回发或回调参数无效》：user1/9/archives/2007/3265.html
2007-04-02 20:28:00《在微软中文社区请教“回发或回调参数无效”》：user1/9/archives/2007/3584.html
从2006-11-15开始，到今天，2007-04-04，五个月了。。。
我就是用了一句form1.submit();
先记录这个js
<script type="text/javascript">
function openwin()
{
var win = showModalDialog("dropdownlist2.aspx", "", "dialogWidth:350px; dialogHeight:300px; status:0; help:0");
if (win != null)
{
alert(win);
var control,option;
var tv=new Array();
var text=new Array();
var value=new Array();
controlID="<% =this.DropDownList1.ClientID %>";
control=document.getElementById(controlID);
tv=win.split('||');
text=tv[0].split('|');
value=tv[1].split('|');
var i,n;
n=text.length;
for(i=0;i<n;i++)
{
control.options[control.options.length]=new Option(text[i],value[i]);
}
}
}
</script>
我不知道使用这个js后，我给DropDownList1添加了option后，要怎么注册，就是这个js让我面对回发时验证出错的
现在我不用js添加option了，我让服务器自己做，让服务器自己注册，我使用了一句form1.submit();
<script type="text/javascript">
function openwin()
{
var win = showModalDialog("dropdownlist2.aspx", "", "dialogWidth:350px; dialogHeight:300px; status:0; help:0");
if (win != null)
{
alert(win);
var controlID, control;
controlID="<% =this.hfAddListItem.ClientID %>";
control=document.getElementById(controlID);
control.value=win;
form1.submit();
}
}
</script>
在这里，我使用了一个HiddenField控件做为开关变量，在js里给他赋值，在cs里使用后清空
我给出我的两个页面的完整测试代码，在测试中，我测试了直接放在页面上的DropDownList和放在FormView里的DropDownList：
dropdownlist.aspx
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="dropdownlist.aspx.cs" Inherits="test_dropdownlist" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>使用模态窗口返回数据，刷新DropDownList</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<script type="text/javascript">
function openwin()
{
var win = showModalDialog("dropdownlist2.aspx", "", "dialogWidth:350px; dialogHeight:300px; status:0; help:0");
if (win != null)
{
alert(win);
var controlID, control;
controlID="<% =this.hfAddListItem.ClientID %>";
control=document.getElementById(controlID);
control.value=win;
form1.submit();
}
}
</script>
<input id="Button1" type="button" value="打开模态窗口" onclick="openwin();" />
<asp:Label ID="Label1" runat="server"></asp:Label>
<br />
数据：<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="TextBox1"
ErrorMessage="请输入数据"></asp:RequiredFieldValidator><br />
服务器端列表：<asp:DropDownList ID="DropDownList1" runat="server">
<asp:ListItem>第一项</asp:ListItem>
</asp:DropDownList>
<asp:Button ID="Button3" runat="server" OnClick="Button3_Click" Text="刷新" /><br />
<asp:Button ID="Button2" runat="server" Text="提交数据到服务器" OnClick="Button2_Click" />
<asp:HiddenField ID="hfAddListItem" runat="server" />
<asp:SqlDataSource ID="sdsAdd" runat="server" ConnectionString="<%$ ConnectionStrings:TTOAConnectionString %>"
InsertCommand="insert into t_table (bb) values (@bb)" SelectCommand="select tid,bb from t_table where tid=0">
<InsertParameters>
<asp:Parameter Name="bb" />
</InsertParameters>
</asp:SqlDataSource>
<asp:FormView ID="FormView1" runat="server" DataKeyNames="tid" DataSourceID="sdsAdd"
DefaultMode="Insert">
<InsertItemTemplate>
数据：<asp:TextBox ID="bbTextBox" runat="server" Text='<%# Bind("bb") %>'></asp:TextBox>
<br />
列表：<asp:DropDownList ID="DropDownList2" runat="server"></asp:DropDownList>
<br />
<asp:Button ID="InsertButton" runat="server" CausesValidation="True" CommandName="Insert" Text="插入"></asp:Button>
</InsertItemTemplate>
</asp:FormView>
</div>
</form>
</body>
</html>
dropdownlist.aspx.cs
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class test_dropdownlist : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
string tvStr;
tvStr = hfAddListItem.Value;
if (tvStr.Length > 0)
{
string[] tv;
string[] text;
string[] value;
tv = tvStr.Split('*');
text = tv[0].Split('|');
value = tv[1].Split('|');
int i, n;
n = text.Length;
for (i = 0; i < n; i++)
{
DropDownList1.Items.Add(new ListItem(text[i], value[i]));
}
//刷新FormView里的DropDownList
DropDownList ddl = new DropDownList();
ddl = (DropDownList)FormView1.FindControl("DropDownList2");
if (ddl != null)
{
for (i = 0; i < n; i++)
{
ddl.Items.Add(new ListItem(text[i], value[i]));
}
}
//把hidden控件置空
hfAddListItem.Value = "";
}
}
}
protected void Button2_Click(object sender, EventArgs e)
{
//提交数据
string s;
s = TextBox1.Text;
s += "<br>共有列表：" + DropDownList1.Items.Count.ToString();
Label1.Text=s;
}
protected void Button3_Click(object sender, EventArgs e)
{
string tvStr;
tvStr = TextBox1.Text;
if (tvStr.Length > 0)
{
string[] tv;
string[] text;
string[] value;
tv = tvStr.Split('*');
text = tv[0].Split('|');
value = tv[1].Split('|');
int i, n;
n = text.Length;
for (i = 0; i < n; i++)
{
DropDownList1.Items.Add(new ListItem(text[i], value[i]));
}
}
}
}
dropdownlist2.aspx
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="dropdownlist2.aspx.cs" Inherits="test_dropdownlist2" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>dropdownlist的模态窗口</title>
<script language="JavaScript">
window.name="MyModalDialog";
</script>
</head>
<body>
<form id="form1" runat="server" target="MyModalDialog">
<div>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="添加" />
<asp:Button ID="Button4" runat="server" OnClick="Button4_Click" Text="确认返回" />
<input id="Button5" type="button" value="关闭" onclick="if(confirm('确认放弃吗？')) window.close();" /><br />
<asp:ListBox ID="ListBox1" runat="server" Rows="10" Width="300px"></asp:ListBox>
<asp:Button ID="Button2" runat="server" OnClick="Button2_Click" Text="删除选择" />
<asp:Button ID="Button3" runat="server" OnClick="Button3_Click" Text="全部删除" /></div>
</form>
</body>
</html>
dropdownlist2.aspx.cs
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class test_dropdownlist2 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
//添加
string s;
s = TextBox1.Text;
ListBox1.Items.Add(new ListItem(s, s));
}
protected void Button2_Click(object sender, EventArgs e)
{
//删除选择
ListItem li = new ListItem();
li = ListBox1.SelectedItem;
if (li != null)
{
ListBox1.Items.Remove(li);
}
}
protected void Button3_Click(object sender, EventArgs e)
{
//删除全部
ListBox1.Items.Clear();
}
protected void Button4_Click(object sender, EventArgs e)
{
//确认返回
//window.returnValue = ""; window.close();
string text = "", value = "";
foreach (ListItem li in ListBox1.Items)
{
text += li.Text + "|";
value += li.Value + "|";
}
if (text.Length > 0)
{
text = text.Remove(text.Length - 1);
value = value.Remove(value.Length - 1);
text = text + "*" + value;
}
Response.Write("<script type='text/javascript'>window.returnValue = '" + text + "'; window.close();</script>");
}
}
