TextBox.TextChanged Event
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Occurs when the user changes the text of a TextBox. This API is obsolete. For information about how to develop ASP.NET mobile applications, see Mobile Apps & Sites with ASP.NET.
public:
event EventHandler ^ TextChanged;
public event EventHandler TextChanged;
member this.TextChanged : EventHandler
Public Custom Event TextChanged As EventHandler
Event Type
Examples
The following example demonstrates how to use the TextChanged event to change the items in a SelectionList.
<%@ Page Language="C#"
Inherits="System.Web.UI.MobileControls.MobilePage" %>
<%@ Register TagPrefix="mobile"
Namespace="System.Web.UI.MobileControls"
Assembly="System.Web.Mobile" %>
<script runat="server">
void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
// Add items to the list
SelectionList1.Items.Add(new
MobileListItem("Verify transactions","Done"));
SelectionList1.Items.Add(new
MobileListItem("Check balance sheet","Scheduled"));
SelectionList1.Items.Add(new
MobileListItem("Call customer", "Done"));
SelectionList1.Items.Add(new
MobileListItem("Send checks", "Pending"));
SelectionList1.Items.Add(new
MobileListItem("Send report", "Pending"));
SelectionList1.Items.Add(new
MobileListItem("Attend meeting", "Scheduled"));
// Show all items in list
SelectionList1.Rows = SelectionList1.Items.Count;
}
}
void TextChanged(object sender, EventArgs e)
{
// Called during PostBack, if changed
string task = TextBox1.Text;
string status = TextBox2.Text;
if (task.Length > 0 && status.Length > 0)
{
MobileListItem li = new MobileListItem(task, status);
// Remove the item if it exists
if (SelectionList1.Items.Contains(li))
SelectionList1.Items.Remove(li);
else
// Add the item if it does not exist
SelectionList1.Items.Add(li);
// Clear the text boxes
TextBox1.Text = String.Empty;
TextBox2.Text = String.Empty;
}
// Display all items.
SelectionList1.Rows = SelectionList1.Items.Count;
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<body>
<mobile:Form id="Form1" runat="server">
<mobile:Label Id="Label1" runat="server">
Create a new Task with Status</mobile:Label>
<mobile:SelectionList runat="server" BreakAfter="true"
SelectType="ListBox"
id="SelectionList1" />
<mobile:Label Id="Label2" runat="server"
Text="Enter the Task name" />
<mobile:TextBox runat="server" id="TextBox1"
OnTextChanged="TextChanged" />
<mobile:Label Id="Label3" runat="server"
Text="Enter the Task status" />
<mobile:TextBox runat="server" id="TextBox2" />
<mobile:Command ID="Command1" runat="server"
Text="Submit" />
</mobile:Form>
</body>
</html>
<%@ Page Language="VB"
Inherits="System.Web.UI.MobileControls.MobilePage" %>
<%@ Register TagPrefix="mobile"
Namespace="System.Web.UI.MobileControls"
Assembly="System.Web.Mobile" %>
<script runat="server">
Protected Sub Page_Load(ByVal byvalsender As Object, _
ByVal e As EventArgs)
If Not IsPostBack Then
' Add items to the list
SelectionList1.Items.Add(New _
MobileListItem("Verify transactions", "Done"))
SelectionList1.Items.Add(New _
MobileListItem("Check balance sheet", "Scheduled"))
SelectionList1.Items.Add(New _
MobileListItem("Call customer", "Done"))
SelectionList1.Items.Add(New _
MobileListItem("Send checks", "Pending"))
SelectionList1.Items.Add(New _
MobileListItem("Send report", "Pending"))
SelectionList1.Items.Add(New _
MobileListItem("Attend meeting", "Scheduled"))
' Show all items in list
SelectionList1.Rows = SelectionList1.Items.Count
End If
End Sub
Private Sub TextChanged(ByVal sender As Object, _
ByVal e As EventArgs)
' Called during PostBack, if changed
Dim task As String = TextBox1.Text
Dim status As String = TextBox2.Text
If (task.Length > 0 AndAlso status.Length > 0) Then
Dim li As New MobileListItem(task, status)
' Remove the item if it exists
If (SelectionList1.Items.Contains(li)) Then
SelectionList1.Items.Remove(li)
Else
' Add the item if it does not exist
SelectionList1.Items.Add(li)
End If
' Clear the text boxes
TextBox1.Text = String.Empty
TextBox2.Text = String.Empty
End If
' Display all items.
SelectionList1.Rows = SelectionList1.Items.Count
End Sub
</script>
<html xmlns="http:'www.w3.org/1999/xhtml" >
<body>
<mobile:Form id="Form1" runat="server">
<mobile:Label Id="Label1" runat="server">
Create a new Task with Status</mobile:Label>
<mobile:SelectionList runat="server"
SelectType="ListBox"
id="SelectionList1" />
<mobile:Label Id="Label2" runat="server"
Text="Enter the Task name" />
<mobile:TextBox runat="server" id="TextBox1"
OnTextChanged="TextChanged" />
<mobile:Label Id="Label3" runat="server"
Text="Enter the Task status" />
<mobile:TextBox runat="server" id="TextBox2" />
<mobile:Command ID="Command1" runat="server"
Text="Submit" />
</mobile:Form>
</body>
</html>
Remarks
When the user changes the text of a TextBox, this event is not raised immediately. The form must contain a Command to initiate a postback event that raises the TextChanged event.