Represents a control to display a list of items.
The Wisej.Web.ListBox control displays a list of strings or data-bound values, allowing the user to select one or multiple options.
The ListBox control supports the inline property. This allows an application to set a label in relation to a ListBox control without having to create an additional Label control.
Data binding is fully supported, including formatting and conversion of the value, through the default infrastructure.
In addition to binding the value (Text, or SelectedItem or SelectedValue bindable properties), the ListBox control also supports data binding to populate the list using the DataSource property in conjunction with the DisplayMember, ValueMember, ToolTipMember and IconMember properties.
When the ShowToolTips property is set to true, the ComboBox control uses the name specified in the ToolTipMember to read the tooltip text to display next to each item in the drop down list.
The ListBox control allows users to define one of several different selection modes for the control's configuration.
You can see the different configuration options shown below.
The ListBox control includes lazy loading support. Lazy loading works by sending the minimum number of records to the browser that is required for display within the control.
Lazy loading will significantly reduce waiting times related to rendering on the browser and network congestion caused by transferring large datasets from the server to the client (browser).
The ListBox control has the ability to use virtual scrolling, a feature that only renders the list items currently visible in the browser.
Using this option can drastically reduce the amount of time spent rendering in the browser for large datasets. For a List containing 25,000 strings, the effect will be a noticeable difference of several seconds.
Try the following sample code to test the loading times:
There are a few different ways to populate a ListBox control.
You can add a list of strings using the Items property of the ListBox control.
Alternatively, you can assign a list of items using the DataSource property of the control.
Icon
Building off of the previous code snippet, it is easy to add an icon to the ListBox items.
The icon paths specified in each object refer to the location of the image relative to the root of the project.
The above code will result in something similar to the following:
If you are working currencies, dates, or other forms of data, you might want to utilize the FormatString property of the ListBox control.
You only need to specify FormattingEnabled = true when using a DisplayMember.
The result will look something like this (dependent on system currency):
None
No items can be selected.
One
Only one item can be selected.
MultiSimple
Multiple items can be selected.
MultiExtended
Multiple items can be selected, and the user can use the SHIFT, CTRL, and arrow keys to make selections.
Class name
wisej.web.ListBox for the ListBox. wisej.web.listbox.ListItem for each list box item.
Theme appearance
"list", "listitem" for the items in the list box, see Themes.
ListBox child components
"scrollbar-x" is the horizontal scrollbar and "scrollbar-y" is the vertical scrollbar. See JavaScript.
List item child components
"checkbox" is the list item's checkbox. "icon" is the list item's icon. See JavaScript.
ToolContainer state
"listbox", see Embedded Tools.
Source code
private void Page1_Load(object sender, EventArgs e)
{
var myList = new List<string>();
for (int i=0; i<25000; i++)
{
myList.Add($"String {i}");
}
this.listBox1.VirtualScroll = true;
this.listBox1.DataSource = myList;
}Private Sub Page1_Load(object sender, EventArgs e) Handles Page1.Load
Dim myList As New List(Of String)
For i = 0 To 25000
myList.Add($"String {i}")
Next
Me.listBox1.VirtualScroll = true
Me.listBox1.DataSource = myList
End Subprivate void button1_Click(object sender, EventArgs e)
{
this.listBox1.Items.AddRange(new[] {
"Eggs",
"Milk",
"Carrots"
});
}Option Strict Off
Private Sub Button1_Click(sender as Object, e As EventArgs) Handles Button1.Click
Me.listBox1.Items.AddRange({
"Eggs",
"Milk",
"Carrots"
})
End Subprivate void button1_Click(object sender, EventArgs e)
{
var myList = new List<dynamic>()
{
new { id = 1, name = "John" },
new { id = 2, name = "Jane" },
new { id = 3, name = "Sally" }
};
this.listBox1.ValueMember = "id";
this.listBox1.DisplayMember = "name";
this.listBox1.DataSource = myList;
}Option Strict Off
Private Sub Button1_Click(sender as Object, e As EventArgs) Handles Button1.Click
{
Dim myList As New List(Of Object) From
{
New With { .id = 1, .name = "John"},
New With { .id = 2, .name = "Jane"},
New With { .id = 3, .name = "Sally"}
}
Me.listBox1.ValueMember = "id"
Me.listBox1.DisplayMember = "name"
Ne.listBox1.DataSource = myList
End Subprivate void button1_Click(object sender, EventArgs e)
{
var myList = new List<dynamic>()
{
new { id = 1, name = "John", icon = "Images/People/1.png" },
new { id = 2, name = "Jane", icon = "Images/People/2.png" },
new { id = 3, name = "Sally", icon = "Images/People/3.png" }
};
this.listBox1.IconMember = "icon";
this.listBox1.DisplayMember = "name";
this.listBox1.DataSource = myList;
}Option Strict Off
Private Sub Button1_Click(sender as Object, e As EventArgs) Handles Button1.Click
{
Dim myList As New List(Of Object) From
{
New With { .id = 1, .name = "John", .icon = "Images/People/1.png" },
New With { .id = 2, .name = "Jane", .icon = "Images/People/2.png" },
New With { .id = 3, .name = "Sally", .icon = "Images/People/3.png" }
}
Me.listBox1.IconMember = "icon"
Me.listBox1.DisplayMember = "name"
Ne.listBox1.DataSource = myList
End Subprivate void button1_Click(object sender, EventArgs e)
{
var myList = new List<dynamic>()
{
new { id = 1, name = "John", payment = 32.53 },
new { id = 2, name = "Jane", payment = 235.53 },
new { id = 3, name = "Sally", payment = 45.21 }
};
this.listBox1.FormatString = "C2";
this.listBox1.FormattingEnabled = true;
this.listBox1.DisplayMember = "payment";
this.listBox1.DataSource = myList;
}Option Strict Off
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim myList As New List(Of Object) From
{
New With { .id = 1, .name = "John", .payment = 32.53 }
New With { .id = 2, .name = "Jane", .payment = 235.53 }
New With { .id = 3, .name = "Sally", .payment = 45.21 }
}
Me.listBox1.FormatString = "C2"
Me.listBox1.FormattingEnabled = true
Me.listBox1.DisplayMember = "payment"
Me.listBox1.DataSource = myList
End Sub
Displays a ListBox in which a check box is displayed to the left of each item.
The Wisej.Web.CheckedListBox is based upon the Wisej.Web.ListBox control but includes a checkbox on the left side of each list item.
Each item within the CheckedListBox control has a checkbox on the left side of it.
The CheckOnClick property of the CheckedListBox control can also be set to accept check state changes on a list item.
Adding Checkboxes to the CheckedListBox control is easy. See the following code snippet:
The above code snippet results in:
Class name
wisej.web.CheckedListBox for the CheckedListBox. wisej.web.listbox.ListItem for each list box item.
Theme appearance
"list", "listitem" for the items in the list box. See Themes.
ListBox child components
"scrollbar-x" is the horizontal scrollbar and "scrollbar-y" is the vertical scrollbar. See JavaScript.
List Item child components
"checkbox" is the checkbox shown in each list item. "icon" is the icon shown in each list item. See JavaScript.
ToolContainer state
"listbox", see Embedded Tools.
Source code
private void Page1_Load(object sender, EventArgs e)
{
var myGroceries = new List<dynamic>() {
new { name = "Eggs", price = 1.00, purchased = true },
new { name = "Apples", price = 0.50, purchased = false },
new { name = "Milk", price = 2.00, purchased = true },
new { name = "Juice", price = 3.00, purchased = false }
};
this.checkedListBox1.DataSource = myGroceries;
this.checkedListBox1.DisplayMember = "name";
this.checkedListBox1.CheckStateMember = "purchased";
}Private Sub Page1_Load(ByVal sender As Object, ByVal e As EventArgs)
Dim myGroceries = New List(Of Object)() From {
New With {
.name = "Eggs",
.price = 1.0,
.purchased = True
},
New With {
.name = "Apples",
.price = 0.5,
.purchased = False
},
New With {
.name = "Milk",
.price = 2.0,
.purchased = True
},
New With {
.name = "Juice",
.price = 3.0,
.purchased = False
}
}
Me.checkedListBox1.DataSource = myGroceries
Me.checkedListBox1.DisplayMember = "name";
Me.checkedListBox1.CheckStateMember = "purchased";
End Sub
