pratikshahse
asked on
multi line select in list box in asp.net
I have an ASP.NET form in which I am using a listbox. I have set the selectionmode property to "Multiple". what i want to do is all the items that are selected from the listbox i want to pass it to a variable with comma as a seprator. But no matter what I select it only passes me the value for the first item in the list box whether its selected or not selected.
Here an example
List box1
item1 selected
item2 selected
item3
item4 selected
item5
item6 selected.
out of the four items that are selected it will only pass the value of item1 in variable.
here is the code that i am using
For i = 1 To listbox1.Items.Count
If listbox1.Items(i - 1).Selected = True Then
strsub = strsub & "," & listbox1.items(i-1).Text
End If
Next
Here an example
List box1
item1 selected
item2 selected
item3
item4 selected
item5
item6 selected.
out of the four items that are selected it will only pass the value of item1 in variable.
here is the code that i am using
For i = 1 To listbox1.Items.Count
If listbox1.Items(i - 1).Selected = True Then
strsub = strsub & "," & listbox1.items(i-1).Text
End If
Next
ASKER
If Not IsPostBack = True Then
Dim brand As String
cn = New OracleConnection(Configura
sql = "select item_family_brand_text,ite
mycommand = New OracleDataAdapter(sql, cn)
mydataset = New DataSet
mycommand.Fill(mydataset)
drpbrand_nm.DataSource = mydataset
drpbrand_nm.DataValueField
drpbrand_nm.DataTextField = "item_family_brand_text"
drpbrand_nm.DataBind()
mycommand.Dispose()
mydataset.Dispose()
brand = drpbrand_nm.SelectedValue
sql = "select item_family_brand_code,ite
mycommand = New OracleDataAdapter(sql, cn)
mydataset = New DataSet
mycommand.Fill(mydataset)
listbox1.DataSource = mydataset
listbox1.DataValueField = "item_family_brand_code"
listbox1.DataTextField = "item_brand_text"
listbox1.DataBind()
mycommand.Dispose()
mydataset.Dispose()
End If
Dim brand As String
cn = New OracleConnection(Configura
sql = "select item_family_brand_text,ite
mycommand = New OracleDataAdapter(sql, cn)
mydataset = New DataSet
mycommand.Fill(mydataset)
drpbrand_nm.DataSource = mydataset
drpbrand_nm.DataValueField
drpbrand_nm.DataTextField = "item_family_brand_text"
drpbrand_nm.DataBind()
mycommand.Dispose()
mydataset.Dispose()
brand = drpbrand_nm.SelectedValue
sql = "select item_family_brand_code,ite
mycommand = New OracleDataAdapter(sql, cn)
mydataset = New DataSet
mycommand.Fill(mydataset)
listbox1.DataSource = mydataset
listbox1.DataValueField = "item_family_brand_code"
listbox1.DataTextField = "item_brand_text"
listbox1.DataBind()
mycommand.Dispose()
mydataset.Dispose()
End If
The following code:
Public Class WebForm1
Inherits System.Web.UI.Page
#Region " Web Form Designer Generated Code "
'This call is required by the Web Form Designer.
<System.Diagnostics.Debugg
End Sub
Protected WithEvents ListBox1 As System.Web.UI.WebControls.
Protected WithEvents Button1 As System.Web.UI.WebControls.
'NOTE: The following placeholder declaration is required by the Web Form Designer.
'Do not delete or move it.
Private designerPlaceholderDeclara
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
'CODEGEN: This method call is required by the Web Form Designer
'Do not modify it using the code editor.
InitializeComponent()
End Sub
#End Region
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'Put user code to initialize the page here
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim item As ListItem
Dim s As String = String.Empty
For Each item In ListBox1.Items
If item.Selected Then
If s <> String.Empty Then
s &= ","
End If
s &= item.Text
End If
Next
Response.Write("Results=" & s)
End Sub
End Class
worked great for me.
I selected A,C, and D
The results screen showed:
Results=A,C,D
HTH,
Shane
Public Class WebForm1
Inherits System.Web.UI.Page
#Region " Web Form Designer Generated Code "
'This call is required by the Web Form Designer.
<System.Diagnostics.Debugg
End Sub
Protected WithEvents ListBox1 As System.Web.UI.WebControls.
Protected WithEvents Button1 As System.Web.UI.WebControls.
'NOTE: The following placeholder declaration is required by the Web Form Designer.
'Do not delete or move it.
Private designerPlaceholderDeclara
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
'CODEGEN: This method call is required by the Web Form Designer
'Do not modify it using the code editor.
InitializeComponent()
End Sub
#End Region
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'Put user code to initialize the page here
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim item As ListItem
Dim s As String = String.Empty
For Each item In ListBox1.Items
If item.Selected Then
If s <> String.Empty Then
s &= ","
End If
s &= item.Text
End If
Next
Response.Write("Results=" & s)
End Sub
End Class
worked great for me.
I selected A,C, and D
The results screen showed:
Results=A,C,D
HTH,
Shane
I added a button to a web form, and a ListBox, with Mode set to Multiple.
In the Code Behind, I have thsi code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim strsub As String
For i As Integer = 1 To ListBox1.Items.Count
If ListBox1.Items(i - 1).Selected = True Then
strsub = strsub & "," & ListBox1.Items(i - 1).Text
End If
Next
Label1.Text = strsub
End Sub
and the label control shows the expected result, when multiple itmes from the ListBox are selected.
AW
In the Code Behind, I have thsi code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim strsub As String
For i As Integer = 1 To ListBox1.Items.Count
If ListBox1.Items(i - 1).Selected = True Then
strsub = strsub & "," & ListBox1.Items(i - 1).Text
End If
Next
Label1.Text = strsub
End Sub
and the label control shows the expected result, when multiple itmes from the ListBox are selected.
AW
ASKER CERTIFIED SOLUTION
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Set the AutoPostBack property of the listbox to true.
_______________
Nayer Naguib
_______________
Nayer Naguib
SStory: When you have some "harcoded" items in the listbox, you do not need to set the AutoPostBack property to true. That's why your code worked.
_______________
Nayer Naguib
_______________
Nayer Naguib
pratikshahse, the main problem was that the http request with the multiselect
listbox looks like this:
GET /bla.asp?select1=h1&select
Accept: ...
Accept-Language: ...
Accept-Encoding: ...
User-Agent: ...
Host: ...
Connection: ...
with the html like:
<SELECT name=select1 multiple>
<option selected>opt1</option>
<option>opt2</option>
<option selected>opt3</option>
<option selected>opt4</option>
<option>opt5</option>
<option selected>opt6</option>
</SELECT>
that means the request contains repeated "name=value" pairs with the same
name string:
"GET /bla.asp?select1=h1&select
(select1=h1 & select1=h3 & select1=h4 & select1=h6 )
If you don't find the way how to get the selected items, the last solution would
be to check the raw url, and to split those name=value pairs into your comma
separated list.
listbox looks like this:
GET /bla.asp?select1=h1&select
Accept: ...
Accept-Language: ...
Accept-Encoding: ...
User-Agent: ...
Host: ...
Connection: ...
with the html like:
<SELECT name=select1 multiple>
<option selected>opt1</option>
<option>opt2</option>
<option selected>opt3</option>
<option selected>opt4</option>
<option>opt5</option>
<option selected>opt6</option>
</SELECT>
that means the request contains repeated "name=value" pairs with the same
name string:
"GET /bla.asp?select1=h1&select
(select1=h1 & select1=h3 & select1=h4 & select1=h6 )
If you don't find the way how to get the selected items, the last solution would
be to check the raw url, and to split those name=value pairs into your comma
separated list.
h1, h2, h3 are actually opt1, opt2, opt3...
a typo.. sorry..
a typo.. sorry..
I posted before I'd seen the author show the loading code. I didn't know it was coming from a database based on the original question.
ASKER
AW
if i use your code then it does not even go inside "if". everytime i select something and hit button1 it would reload the page with nothing selected.
if i use your code then it does not even go inside "if". everytime i select something and hit button1 it would reload the page with nothing selected.
ASKER
Nayer Naguib
I tried making autopostback = true but that wont allow me to insert more than one item.
I tried making autopostback = true but that wont allow me to insert more than one item.
Three settings on your listbox are important: SelectionMode = SelectionMode.Multiple | AutoPostBack=True | EnableViewState=True
EnableViewState=True is what maintains selection state across postback(s)
I just whipped up a page that binds a listbox from a SQL stored proc that returns ten most recent updates to a table, then rather than concatenating a string, enters each value and a vbCrLf in a multiline textbox (just so I could more easily see the correlation in testing). Here's my code, which works perfectly on this end.
Imports System.Data.SqlClient
Public Class WebForm6
Inherits System.Web.UI.Page
#Region " Web Form Designer Generated Code "
'This call is required by the Web Form Designer.
<System.Diagnostics.Debugg
End Sub
Protected WithEvents tb1 As System.Web.UI.WebControls.
Protected WithEvents lbtest As System.Web.UI.WebControls.
'NOTE: The following placeholder declaration is required by the Web Form Designer.
'Do not delete or move it.
Private designerPlaceholderDeclara
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
'CODEGEN: This method call is required by the Web Form Designer
'Do not modify it using the code editor.
InitializeComponent()
End Sub
#End Region
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
If Not Page.IsPostBack Then
lbtest.AutoPostBack = True
lbtest.SelectionMode = ListSelectionMode.Multiple
Dim sCon As New SqlConnection(Configuratio
Dim sCmd As New SqlCommand("[sp_LastTenUpd
sCmd.CommandType = CommandType.StoredProcedur
sCon.Open()
lbtest.DataSource = sCmd.ExecuteReader
lbtest.DataMember = 0
lbtest.DataTextField = ("tmUpdate").ToString
lbtest.DataValueField = ("tmStart").ToString
lbtest.DataBind()
sCon.Close()
End If
Dim i As Integer
tb1.Text = ""
For i = 0 To (lbtest.Items.Count - 1)
If lbtest.Items(i).Selected = True Then
tb1.Text &= lbtest.Items(i).Text & vbCrLf
End If
Next
End Sub
End Class
EnableViewState=True is what maintains selection state across postback(s)
I just whipped up a page that binds a listbox from a SQL stored proc that returns ten most recent updates to a table, then rather than concatenating a string, enters each value and a vbCrLf in a multiline textbox (just so I could more easily see the correlation in testing). Here's my code, which works perfectly on this end.
Imports System.Data.SqlClient
Public Class WebForm6
Inherits System.Web.UI.Page
#Region " Web Form Designer Generated Code "
'This call is required by the Web Form Designer.
<System.Diagnostics.Debugg
End Sub
Protected WithEvents tb1 As System.Web.UI.WebControls.
Protected WithEvents lbtest As System.Web.UI.WebControls.
'NOTE: The following placeholder declaration is required by the Web Form Designer.
'Do not delete or move it.
Private designerPlaceholderDeclara
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
'CODEGEN: This method call is required by the Web Form Designer
'Do not modify it using the code editor.
InitializeComponent()
End Sub
#End Region
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
If Not Page.IsPostBack Then
lbtest.AutoPostBack = True
lbtest.SelectionMode = ListSelectionMode.Multiple
Dim sCon As New SqlConnection(Configuratio
Dim sCmd As New SqlCommand("[sp_LastTenUpd
sCmd.CommandType = CommandType.StoredProcedur
sCon.Open()
lbtest.DataSource = sCmd.ExecuteReader
lbtest.DataMember = 0
lbtest.DataTextField = ("tmUpdate").ToString
lbtest.DataValueField = ("tmStart").ToString
lbtest.DataBind()
sCon.Close()
End If
Dim i As Integer
tb1.Text = ""
For i = 0 To (lbtest.Items.Count - 1)
If lbtest.Items(i).Selected = True Then
tb1.Text &= lbtest.Items(i).Text & vbCrLf
End If
Next
End Sub
End Class
I'm sorry - in my last post, on the first line I wrote
SelectionMode=SelectionMod
That should have read
SelectionMode=ListSelectio
It's correct in my code sample, as I copied/pasted that directly from Visual Studio, but didn't want you skimming over, typing that in and getting intellisense errors etc...
SelectionMode=SelectionMod
That should have read
SelectionMode=ListSelectio
It's correct in my code sample, as I copied/pasted that directly from Visual Studio, but didn't want you skimming over, typing that in and getting intellisense errors etc...
I have written similar code that does the job, and did not have to set EnableViewState to true. First, it's set to true by default. Second, having this property set to false *clears* the whole listbox after postbacks!
Having the SelectionMode set to Multiple is the only other requirement, which the author has already done.
_______________
Nayer Naguib
Having the SelectionMode set to Multiple is the only other requirement, which the author has already done.
_______________
Nayer Naguib
pratikshahse: To avoid this behavior of the ASP .NET listbox control, you need to make sure that all added items will have unique Text **and** Value property values.
_______________
Nayer Naguib
_______________
Nayer Naguib
AW