listbox refresh如何实现？vb
listbox refresh如何实现？language = vb
刚学.net，遇到这样一个问题，往一个listbox里添加listItem，但是添加进去了不能显示出来，需要再次添加数据的时候上一次添加进去的才显示出来。
搜索了MSDN和CSDN的相关资料，并没有发现能解决偶这个问题的比较清晰的答案，希望大家帮帮忙。如果要写类请将类的写法及页面中引用的方法告知，谢谢。
问题点数：100、回复次数：13Top
1 楼dh20156（风之石）回复于 2006-03-08 16:55:27 得分 0
麻烦各位兄弟姐妹关注一下，谢谢。Top
2 楼xcz1943（小钊）回复于 2006-03-08 16:57:32 得分 20
你怎么添加的，
public sub Page_load(byval sender as object,....)
Addlist()
end sub
public sub Addlist()
......
'在这里添加你要添加的代码
end subTop
3 楼dh20156（风之石）回复于 2006-03-08 17:07:12 得分 0
这是我添加东西的SUB，我是从一个hidden里取值给listbox2的，然后就发现只有在下一次添加的时候上一次添加的值才会在listbox2里显示出来。
Sub ShowThis(send as object,e as eventArgs)
dim sv as string
sv = listbox1.selectedItem.value
dim scriptstr as string
scriptstr = "<script>"
scriptstr = scriptstr + "wPopup = window.open('about:blank','','width=300,height=180,left=200,top=200,menubar=no,resizeable=no,scrollbars=no,toolbar=no');"
scriptstr = scriptstr + "var wPopupDoc=wPopup.document;"
scriptstr = scriptstr + "wPopupDoc.open();"
scriptstr = scriptstr + "wPopupDoc.write('<html><head></head><body style=""border:none;background:buttonface;"" oncontextmenu=""return false"">');"
scriptstr = scriptstr + "wPopupDoc.write('<table width=""100%"" height=""100%""><tr height=""30""><td><h4 id=""colname"">" + sv + "</h4></td></tr>');"
scriptstr = scriptstr + "wPopupDoc.write('<tr height=""30""><td><b>=</b> <input type=""text"" name=""colval""> </td></tr>');"
scriptstr = scriptstr + "wPopupDoc.write('<tr><td align=""right""><input type=""button"" value="" Submit "" onclick=""window.opener.showcolval();""> <input type=""button"" value="" Close "" onclick=""window.close();""></td></tr></table>');"
scriptstr = scriptstr + "wPopupDoc.write('</body></html>');"
scriptstr = scriptstr + "wPopupDoc.close();"
scriptstr = scriptstr + "<"+"/script>"
Response.Write(scriptstr)
If hidetextbox1.value<>"" then
listbox2.items.add(new listItem(hidetextbox1.value))
'listbox2.Refresh()
hidetextbox1.value = ""
End if
End SubTop
4 楼quanke1981（笨猪先跑）回复于 2006-03-08 17:26:40 得分 0
你的SUB是在什么时候调用的？Top
5 楼dh20156（风之石）回复于 2006-03-08 18:18:00 得分 0
这个Sub ShowThis 是在listbox1选择后然后点击一个按钮时调用的。Top
6 楼dh20156（风之石）回复于 2006-03-08 18:58:27 得分 0
各位帮帮忙吧，谢谢！只要告诉我listbox如何才能调用Refresh()方法就好了，非常感谢！Top
7 楼cat_hsfz（我的新Blog在http://cathsfz.cnblogs.com）回复于 2006-03-08 19:19:35 得分 20
这个不是刷新问题，而可能是事件调用顺序问题。
ShowThis是某个按钮Click事件的直接执行过程吗？还是这个ShowThis的执行已经晚了（相对于Page的生命周期来说），所以添加的东西没有Render进去？最好贴出ShowThis被调用的调用链。Top
8 楼goody9807（http://goody9807.cnblogs.com）回复于 2006-03-08 19:34:03 得分 20
你Page_Load中如何写的
把的代码贴出来
有事联系
http://cnblogs.com/goody9807Top
9 楼dh20156（风之石）回复于 2006-03-08 20:36:49 得分 0
这是全文代码，用的是Northwind的Products表：
<%@ Language="VB" Debug="True" ValidateRequest="False" EnableEventValidation="false" %>
<html>
<head>
<title>test3.aspx</title>
<style>
body {background:buttonface;font-size:12px;}
td {font-size:12px;}
th {font-size:12px;}
input {font-size:12px;border:1px solid white;}
</style>
<script>
function showcolval(){
var wPopupElements = wPopup.document.all;
var colname = wPopupElements.colname.innerText;
var colvalue = wPopupElements.colval.value;
var cs = colname + "=" + colvalue;
document.all.hidetextbox1.value = cs;
wPopup.close();
}
</script>
</head>
<script language="VB" runat="server">
Sub ShowThis(send as object,e as eventArgs)
If listbox1.selectedIndex >= 0 then
dim sv as string
sv = listbox1.selectedItem.value
dim scriptstr as string
scriptstr = "<script>"
scriptstr = scriptstr + "wPopup = window.open('about:blank','','width=300,height=180,left=200,top=200,menubar=no,resizeable=no,scrollbars=no,toolbar=no');"
scriptstr = scriptstr + "var wPopupDoc=wPopup.document;"
scriptstr = scriptstr + "wPopupDoc.open();"
scriptstr = scriptstr + "wPopupDoc.write('<html><head></head><body style=""border:none;background:buttonface;"" oncontextmenu=""return false"">');"
scriptstr = scriptstr + "wPopupDoc.write('<table width=""100%"" height=""100%""><tr height=""30""><td><h4 id=""colname"">" + sv + "</h4></td></tr>');"
scriptstr = scriptstr + "wPopupDoc.write('<tr height=""30""><td><b>=</b> <input type=""text"" name=""colval""> </td></tr>');"
scriptstr = scriptstr + "wPopupDoc.write('<tr><td align=""right""><input type=""button"" value="" Submit "" onclick=""window.opener.showcolval();""> <input type=""button"" value="" Close "" onclick=""window.close();""></td></tr></table>');"
scriptstr = scriptstr + "wPopupDoc.write('</body></html>');"
scriptstr = scriptstr + "wPopupDoc.close();"
scriptstr = scriptstr + "<"+"/script>"
Response.Write(scriptstr)
End if
If hidetextbox1.value<>"" then
listbox2.items.add(new listItem(hidetextbox1.value))
'listbox2.Refresh()
hidetextbox1.value = ""
End if
End Sub
Sub ClearLayer(send as object,e as eventArgs)
If listbox2.selectedIndex >= 0 then
listbox2.items.remove(listbox2.selectedItem.value)
End if
End Sub
</script>
<body>
<center>
<form name="form1" method="post" action="test3.aspx" runat="server">
<fieldset>
<legend>Filter by queryString</legend>
<asp:GridView id="GridView1" DataSourceID="SqlDataSource1" AllowPaging="True" PageSize="20" AllowSorting="True" AutoGenerateColumns="True" runat="server"/>
<asp:SqlDataSource id="SqlDataSource1" SelectCommand="Select Top 100 * From [Products] Where ([ProductID] = @ProductID) OR ([ProductName] Like '%' + @ProductName + '%') OR ([SupplierID] = @SupplierID) OR ([CategoryID] = @CategoryID) OR ([QuantityPerUnit] Like '%' + @QuantityPerUnit + '%') OR ([UnitPrice] <= CONVERT(Money,@UnitPrice)) OR ([UnitsInStock] <= CONVERT(int,@UnitsInStock)) OR ([UnitsOnOrder] <= CONVERT(int,@UnitsOnOrder)) OR ([ReorderLevel] <= CONVERT(int,@ReorderLevel))" ConnectionString="<%$ ConnectionStrings:Northwind %>" runat="server">
<SelectParameters>
<asp:QueryStringParameter Name="ProductID" QueryStringField="ProductID" DefaultValue="0" />
<asp:QueryStringParameter Name="ProductName" QueryStringField="ProductName" DefaultValue="\" />
<asp:QueryStringParameter Name="SupplierID" QueryStringField="SupplierID" DefaultValue="0" />
<asp:QueryStringParameter Name="CategoryID" QueryStringField="CategoryID" DefaultValue="0" />
<asp:QueryStringParameter Name="QuantityPerUnit" QueryStringField="QuantityPerUnit" DefaultValue="\" />
<asp:QueryStringParameter Name="UnitPrice" QueryStringField="UnitPrice" DefaultValue="-1" />
<asp:QueryStringParameter Name="UnitsInStock" QueryStringField="UnitsInStock" DefaultValue="-1" />
<asp:QueryStringParameter Name="UnitsOnOrder" QueryStringField="UnitsOnOrder" DefaultValue="-1" />
<asp:QueryStringParameter Name="ReorderLevel" QueryStringField="ReorderLevel" DefaultValue="-1" />
</SelectParameters>
</asp:SqlDataSource>
<asp:SqlDataSource id="SqlDataSource2" SelectCommand="Select Top 100 * From [Products] Where ([ProductID] = @ProductID) OR ([ProductName] Like '%' + @ProductName + '%') OR ([SupplierID] = @SupplierID) OR ([CategoryID] = @CategoryID) OR ([QuantityPerUnit] Like '%' + @QuantityPerUnit + '%') OR ([UnitPrice] >= CONVERT(Money,@UnitPrice)) OR ([UnitsInStock] >= CONVERT(int,@UnitsInStock)) OR ([UnitsOnOrder] >= CONVERT(int,@UnitsOnOrder)) OR ([ReorderLevel] >= CONVERT(int,@ReorderLevel))" ConnectionString="<%$ ConnectionStrings:Northwind %>" runat="server">
<SelectParameters>
<asp:QueryStringParameter Name="ProductID" QueryStringField="ProductID" DefaultValue="0" />
<asp:QueryStringParameter Name="ProductName" QueryStringField="ProductName" DefaultValue="\" />
<asp:QueryStringParameter Name="SupplierID" QueryStringField="SupplierID" DefaultValue="0" />
<asp:QueryStringParameter Name="CategoryID" QueryStringField="CategoryID" DefaultValue="0" />
<asp:QueryStringParameter Name="QuantityPerUnit" QueryStringField="QuantityPerUnit" DefaultValue="\" />
<asp:QueryStringParameter Name="UnitPrice" QueryStringField="UnitPrice" DefaultValue="10000000" />
<asp:QueryStringParameter Name="UnitsInStock" QueryStringField="UnitsInStock" DefaultValue="10000000" />
<asp:QueryStringParameter Name="UnitsOnOrder" QueryStringField="UnitsOnOrder" DefaultValue="10000000" />
<asp:QueryStringParameter Name="ReorderLevel" QueryStringField="ReorderLevel" DefaultValue="10000000" />
</SelectParameters>
</asp:SqlDataSource>
</fieldset>
<fieldset>
<legend>Filter by formPost</legend>
<table>
<tr>
<td>
<asp:label id="listLabel1" associatedControlID="listbox1" text="Select The Columns:" font-bold="true" runat="server"/>
<br>
<asp:listbox id="listbox1" DataSourceID="SqlDataSource3" DataTextField="name" width="200px" height="150px" runat="server"/>
<asp:SqlDataSource id="SqlDataSource3" SelectCommand="Select [name] From [syscolumns] Where [id] = object_id(N'[Products]') And [name] <> 'Discontinued'" ConnectionString="<%$ ConnectionStrings:Northwind %>" runat="server" />
<br>
<asp:button id="selectColumn" onclick="ShowThis" text=">>" runat="server"/>
<input type="hidden" id="hidetextbox1" runat="server"/>
</td>
<td>
<asp:label id="listLabel2" associatedControlID="listbox2" text="Selected Columns:" font-bold="true" runat="server"/>
<br>
<asp:listbox id="listbox2" DataTextField="name" width="200px" height="150px" runat="server"/>
<br>
<asp:button id="clearColumn" text="<<" onclick="ClearLayer" runat="server"/>
</td>
</tr>
</fieldset>
</form>
</center>
</body>
</html>Top
10 楼dh20156（风之石）回复于 2006-03-09 14:04:01 得分 0
各位帮帮忙吧，谢了。Top
11 楼nameone（过客）回复于 2006-03-09 14:25:59 得分 20
UPTop
12 楼cuike519（I will be back!）回复于 2006-03-10 09:56:51 得分 20
如果你在Page_Load里面有类似下面的代码：
if(!IsPostBack){
// bind listbox
}
那么你在向ListBox中添加内容後，需要重新绑定数据（再次调用bind listbox的代码），才能体现你的结果。Top
13 楼dh20156（风之石）回复于 2006-03-10 11:14:47 得分 0
TO:cuike519(I will be back!)
偶新学，能否再讲解详细点？或者有什么手册介绍偶下载看看，非常感谢。Top
