ASP.NET SortedList
SortedList objects combines the properties of an object and ArrayList Hashtable object.
Try - Example
SortedList objects
SortedList object contains items with the key / value pairs expressed. SortedList objects automatically sort the items in alphabetical order or numerical order.
By Add () method to add items to the SortedList. By TrimToSize () method to adjust the final size SortedList.
The following code creates a SortedList object called mycountries, and add the four elements:
sub Page_Load
if Not Page.IsPostBack then
dim mycountries=New SortedList
mycountries.Add("N","Norway")
mycountries.Add("S","Sweden")
mycountries.Add("F","France")
mycountries.Add("I","Italy")
end if
end sub
</script>
Data Binding
SortedList object can automatically generate text and values for the following controls:
- asp: RadioButtonList
- asp: CheckBoxList
- asp: DropDownList
- asp: Listbox
To bind data to a RadioButtonList control, first create a RadioButtonList control in an .aspx page (without any asp: ListItem elements):
<body>
<form runat="server">
<asp:RadioButtonList id="rb" runat="server" AutoPostBack="True" />
</form>
</body>
</html>
Then add the script to create the list, and the binding values in the list to the RadioButtonList control:
sub Page_Load
if Not Page.IsPostBack then
dim mycountries=New SortedList
mycountries.Add("N","Norway")
mycountries.Add("S","Sweden")
mycountries.Add("F","France")
mycountries.Add("I","Italy")
rb.DataSource=mycountries
rb.DataValueField="Key"
rb.DataTextField="Value"
rb.DataBind()
end if
end sub
</script>
<html>
<body>
<form runat="server">
<asp:RadioButtonList id="rb" runat="server" AutoPostBack="True" />
</form>
</body>
</html>
Then we add a subroutine, when a user clicks on an item in the RadioButtonList control when the subroutine is executed. When a radio button is clicked, label will appear in the line of text:
Examples
sub Page_Load
if Not Page.IsPostBack then
dim mycountries=New SortedList
mycountries.Add("N","Norway")
mycountries.Add("S","Sweden")
mycountries.Add("F","France")
mycountries.Add("I","Italy")
rb.DataSource=mycountries
rb.DataValueField="Key"
rb.DataTextField="Value"
rb.DataBind()
end if
end sub
sub displayMessage(s as Object,e As EventArgs)
lbl1.text="Your favorite country is: " & rb.SelectedItem.Text
end sub
</script>
<html>
<body>
<form runat="server">
<asp:RadioButtonList id="rb" runat="server"
AutoPostBack="True" onSelectedIndexChanged="displayMessage" />
<p><asp:label id="lbl1" runat="server" /></p>
</form>
</body>
</html>
The demonstration >>