Button.Click Event (System.Web.UI.WebControls)

Click Event

.NET Framework Class Library

Button..::.Click Event

Occurs when the Button control is clicked.

Namespace: System.Web.UI.WebControls
Assembly: System.Web (in System.Web.dll)

Syntax

Visual Basic (Declaration)

Public Event Click As EventHandler

Visual Basic (Usage)

Dim instance As Button
Dim handler As EventHandler

AddHandler instance.Click, handler

public event EventHandler Click

Visual C++

public:
virtual  event EventHandler^ Click {
    void add (EventHandler^ value);
    void remove (EventHandler^ value);
}

JScript

JScript does not support events.

ASP.NET

<asp:Button OnClick="EventHandler" />

Implements

IButtonControl..::.Click

Remarks

The Click event is raised when the Button control is clicked. This event is commonly used when no command name is associated with the Button control (for instance, with a Submit button).

For more information about handling events, see Consuming Events.

Topic	Location
How to: Connect Multiple Events to a Single Event Handler in ASP.NET Web Pages	Building ASP .NET Web Applications
How to: Connect Multiple Events to a Single Event Handler in ASP.NET Web Pages	Building ASP .NET Web Applications
How to: Connect Multiple Events to a Single Event Handler in ASP.NET Web Pages	Building ASP .NET Web Applications in Visual Studio
How to: Connect Multiple Events to a Single Event Handler in ASP.NET Web Pages	Building ASP .NET Web Applications in Visual Studio
How to: Implement Simple Forms Authentication	Building ASP .NET Web Applications
How to: Implement Simple Forms Authentication	Building ASP .NET Web Applications
How to: Implement Simple Forms Authentication	Building ASP .NET Web Applications in Visual Studio
How to: Implement Simple Forms Authentication	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating a Basic Web Page with Code Separation in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Creating a Basic Web Page with Code Separation in Visual Web Developer	Building Applications with Visual Web Developer
Walkthrough: Creating a Basic Web Page with Code Separation in Visual Web Developer	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Validating User Input in a Web Forms Page	Building ASP .NET Web Applications in Visual Studio
Walkthrough: Validating User Input in a Web Forms Page	Building Applications with Visual Web Developer
Walkthrough: Validating User Input in a Web Forms Page	Building ASP .NET Web Applications in Visual Studio

Examples

The following code example demonstrates how to specify and code an event handler for the Click event in order to display a message on the Web page when the Button control is clicked.

Visual Basic

<%@ Page Language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    Sub GreetingBtn_Click(ByVal sender As Object, _
                          ByVal e As EventArgs)

        ' When the button is clicked,
        ' change the button text, and disable it.

        Dim clickedButton As Button = sender
        clickedButton.Text = "...button clicked..."
        clickedButton.Enabled = False

        ' Display the greeting label text.
        GreetingLabel.Visible = True
    End Sub

</script>

<html  >
<head runat="server">
    <title>Button Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <h3>Simple Button Example</h3>

      <asp:Button id="Button1"
           Text="Click here for greeting..."
           OnClick="GreetingBtn_Click" 
           runat="server"/>
      <br />
      <br />
      <asp:Label ID="GreetingLabel" runat="server" 
                 Visible="false" Text="Hello World!" />
    </div>
    </form>
</body>
</html>

<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    void Page_Load(Object sender, EventArgs e)
    {
        // Manually register the event-handling method for
        // the Click event of the Button control.
        Button1.Click += new EventHandler(this.GreetingBtn_Click);
    }

    void GreetingBtn_Click(Object sender,
                           EventArgs e)
    {
        // When the button is clicked,
        // change the button text, and disable it.

        Button clickedButton = (Button)sender;
        clickedButton.Text = "...button clicked...";
        clickedButton.Enabled = false;

        // Display the greeting label text.
        GreetingLabel.Visible = true;
    }

</script>

<html  >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <h3>Simple Button Example</h3>

      <asp:Button id="Button1"
           Text="Click here for greeting..."
           OnClick="GreetingBtn_Click" 
           runat="server"/>
      <br />
      <br />
      <asp:Label ID="GreetingLabel" runat="server" 
                 Visible="false" Text="Hello World!" />
    </div>
    </form>
</body>
</html>

Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

Reference

Button Class

Button Members

System.Web.UI.WebControls Namespace

OnClick

CommandEventHandler

Other Resources

Button Web Server Controls Overview