ASP.Net/Asp Control/ListBox
Содержание
- 1 Add ListItem to ListBox
- 2 Allowing Multiple Selections in a ListBox Control (VB.net)
- 3 asp:listbox: On selected index changed
- 4 Change background color for asp:listbox (VB.net)
- 5 Get selected index from asp:listbox (VB.net)
- 6 Get selected index, text and value from asp:listbox (VB.net)
- 7 Get selected item from ListBox (C#)
- 8 Set static value for asp:listbox (VB.net)
- 9 Using the ListBox to select list items.
Add ListItem to ListBox
<source lang="csharp">
<form runat="server"> <script language="C#" runat="server"> protected void Page_Load(object o, EventArgs e) {
if(!IsPostBack) { ListItem item; item = new ListItem("A"); languageListBox.Items.Add(item); item = new ListItem("B"); languageListBox.Items.Add(item); item = new ListItem("C"); languageListBox.Items.Add(item); languageListBox.Rows = 3; }
} protected void ListBoxSelectionChanged(object o, EventArgs e) {
bool valueSet = false; foreach(ListItem item in languageListBox.Items) { if (item.Selected) { if(valueSet) { favoriteLanguage.Text += ", " + item.Text; } else { favoriteLanguage.Text = item.Text; valueSet = true; } } }
} </script> <asp:ListBox
id="languageListBox" runat="server" SelectionMode="multiple" OnSelectedIndexChanged="ListBoxSelectionChanged" />
Favorite Language: <asp:label runat="server" id="favoriteLanguage" style="color:blue" Text="Not Set" />
<asp:button runat="server" Text="Submit"/> </form>
</source>
Allowing Multiple Selections in a ListBox Control (VB.net)
<source lang="csharp">
<%@ Page Language=VB Debug=true %>
<HTML>
<HEAD>
<TITLE>Allowing Multiple Selections in a ListBox Control</TITLE>
</HEAD>
<form runat="server">
Select a Color:
<asp:listbox id="lb1" runat="server" selectionmode="multiple" rows=4>
<asp:listitem value="Bu">Blue</asp:listitem> <asp:listitem value="Re">Red</asp:listitem> <asp:listitem value="Gr">Green</asp:listitem> <asp:listitem value="Pu" Selected>Purple</asp:listitem> <asp:listitem value="Ba">Black</asp:listitem> <asp:listitem value="Go" text="Gold"/>
</asp:listbox> </form> </BODY> </HTML>
</source>
asp:listbox: On selected index changed
<source lang="csharp">
<%@ Page Language=VB Debug=true %> <script runat=server> Sub lb1_Changed(Sender As Object, E As EventArgs)
lb1.BackColor = System.Drawing.Color.FromName(lb1.SelectedItem.Text)
End Sub
</SCRIPT>
<HTML>
<HEAD>
<TITLE>Writing Code that Fires When the Selection Changes in a ListBox Control</TITLE>
</HEAD>
<form runat="server">
Select a Color:
<asp:listbox id="lb1" runat="server" autopostback="True" onselectedindexchanged="lb1_Changed" rows=3>
<asp:listitem value="Bu">Blue</asp:listitem> <asp:listitem value="Re">Red</asp:listitem> <asp:listitem value="Gr">Green</asp:listitem> <asp:listitem value="Pu" >Purple</asp:listitem> <asp:listitem value="Ba">Black</asp:listitem>
</asp:listbox> </form> </BODY> </HTML>
</source>
Change background color for asp:listbox (VB.net)
<source lang="csharp">
<%@ Page Language=VB Debug=true %> <script runat=server> Sub lb1_Changed(Sender As Object, E As EventArgs)
lb1.BackColor = System.Drawing.Color.FromName(lb1.SelectedItem.Text)
End Sub
</SCRIPT>
<HTML>
<HEAD>
<TITLE>Writing Code that Fires When the Selection Changes in a ListBox Control</TITLE>
</HEAD>
<form runat="server">
Select a Color:
<asp:listbox id="lb1" runat="server" autopostback="True" onselectedindexchanged="lb1_Changed" rows=3>
<asp:listitem value="Bu">Blue</asp:listitem> <asp:listitem value="Re">Red</asp:listitem> <asp:listitem value="Gr">Green</asp:listitem> <asp:listitem value="Pu" >Purple</asp:listitem> <asp:listitem value="Ba">Black</asp:listitem>
</asp:listbox> </form> </BODY> </HTML>
</source>
Get selected index from asp:listbox (VB.net)
<source lang="csharp">
<script runat="server" language="vb">
Sub Page_Load() Dim msg As String = "You have selected:
" If list1.Items(0).Selected Then msg = msg & list1.Items(0).Text & "
" If list1.Items(1).Selected Then msg = msg & list1.Items(1).Text & "
" If list1.Items(2).Selected Then msg = msg & list1.Items(2).Text & "
" Message.Text = msg End Sub</script>
<html>
<head> <title>Drop Down List Example</title> </head> <body> <asp:label id="Message" runat="server"/>
<form runat="server"> Which city do you wish to look at hotels for?
<asp:listbox id="list1" runat="server" selectionmode="multiple"> <asp:listitem>Madrid</asp:listitem> <asp:listitem>Oslo</asp:listitem> <asp:listitem>Lisbon</asp:listitem> </asp:listbox>
<input type="Submit"> </form> </body>
</html>
</source>
Get selected index, text and value from asp:listbox (VB.net)
<source lang="csharp">
<%@ Page Language=VB Debug=true %> <script runat=server> Sub SubmitBtn_Click(Sender As Object, E As EventArgs)
lblDataSelected.Text = "Selected Text: " _ & lb1.SelectedItem.Text & "
Selected Value: " _ & lb1.SelectedItem.Value & "
Selected Index: " _ & lb1.SelectedIndex
End Sub
</SCRIPT>
<HTML>
<HEAD>
<TITLE>Creating a Basic ListBox Control</TITLE>
</HEAD>
<form runat="server">
<asp:label id="lblDataSelected" runat="server"/>
<asp:listbox id="lb1" runat="server" rows=3>
<asp:listitem value="Bu">Blue</asp:listitem> <asp:listitem value="Re">Red</asp:listitem> <asp:listitem value="Gr">Green</asp:listitem> <asp:listitem value="Pu" Selected>Purple</asp:listitem> <asp:listitem value="Ba">Black</asp:listitem> <asp:listitem value="Go" text="Gold"/>
</asp:listbox>
<asp:button id="butOK" text="OK" type="Submit" onclick="SubmitBtn_Click" runat="server"/>
</form>
</BODY>
</HTML>
</source>
Get selected item from ListBox (C#)
<source lang="csharp">
<%@ Page Language="C#" %> <script runat="server">
void Page_Load() { string msgCitiesList = ""; if (Page.IsPostBack == true) if (list1.Items[0].Selected == true) { msgCitiesList = msgCitiesList + list1.Items[0].Text + "
"; } if (list1.Items[1].Selected) { msgCitiesList = msgCitiesList + list1.Items[1].Text + "
"; } if (list1.Items[2].Selected) { msgCitiesList = msgCitiesList + list1.Items[2].Text + "
"; } if (msgCitiesList != "") { Message.Text = "You have selected:
" + msgCitiesList; } else { Message.Text = ""; } }
</script> <html> <head>
<title>List Box Example</title>
</head> <body>
<asp:Label id="Message" runat="server"></asp:Label>
Which city do you wish to look at hotels for?
<form runat="server"> <asp:listbox id="list1" runat="server" selectionmode="multiple"> <asp:listitem>A</asp:listitem> <asp:listitem>B</asp:listitem> <asp:listitem>C</asp:listitem> </asp:listbox>
<input type="submit" value="Submit Query" /> </form>
</body> </html>
</source>
Set static value for asp:listbox (VB.net)
<source lang="csharp">
<%@ Page Language=VB Debug=true %>
<HTML>
<HEAD>
<TITLE>Creating a Basic ListBox Control</TITLE>
</HEAD>
<form runat="server">
Select a Color:
<asp:listbox id="lb1" runat="server" rows=3>
<asp:listitem value="Bu">Blue</asp:listitem> <asp:listitem value="Re">Red</asp:listitem> <asp:listitem value="Gr">Green</asp:listitem> <asp:listitem value="Pu" Selected>Purple</asp:listitem> <asp:listitem value="Ba">Black</asp:listitem> <asp:listitem value="Go" text="Gold"/>
</asp:listbox> </form> </BODY> </HTML>
</source>
Using the ListBox to select list items.
<source lang="csharp">
<%@ Page Language="C#" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> <script runat="server">
protected void btnAdd_Click(object sender, EventArgs e) { ListItem item = lstAllProducts.SelectedItem; if (item != null) { lstAllProducts.Items.Remove(item); lstFavoriteProducts.ClearSelection(); lstFavoriteProducts.Items.Add(item); } } protected void btnRemove_Click(object sender, EventArgs e) { ListItem item = lstFavoriteProducts.SelectedItem; if (item != null) { lstFavoriteProducts.Items.Remove(item); lstAllProducts.ClearSelection(); lstAllProducts.Items.Add(item); } } protected void btnSubmit_Click(object sender, EventArgs e) { foreach (ListItem item in lstFavoriteProducts.Items)lblResults.Text += "
<asp:Button id="btnRemove" Text="<" ToolTip="Remove List Item" Runat="server" OnClick="btnRemove_Click" /> </div> <asp:ListBox id="lstFavoriteProducts" Runat="server" /> </div> <asp:Button id="btnSubmit" Text="Submit Form" Runat="server" OnClick="btnSubmit_Click" /> </p> <asp:Label id="lblResults" EnableViewState="false" Runat="server" /> <asp:SqlDataSource id="srcProducts" SelectCommand="SELECT Id, Title FROM Products" ConnectionString="<%$ ConnectionStrings:Products %>" Runat="server" /> </form> </body> </html> File: Web.config <configuration> <connectionStrings> <add name="Products" connectionString="Data Source=.\SQLEXPRESS; AttachDbFilename=|DataDirectory|MyDatabase.mdf;Integrated Security=True;User Instance=True" /> </connectionStrings> </configuration> </source>