Buttons

A Button Web Server control is a control which we click and release to perform some action. The class hierarchy for the Button control is as follows:

 Object
  Control
   WebControl
    Button

Button Event

The default event of the Button is the Click event which looks like this in code:

Private Sub Button1_Click(ByVal sender As System.Object,_ ByVal e As System.EventArgs) Handles Button1.Click 'Implementation Omitted End Sub

Notable Properties

CausesValidation: Gets/Sets the button that causes validation
CommandArgument: Gets/Sets the command argument which is passed to the command event handler
CommandName: Gets/Sets the command name which is passed to the command event handler
Text: Gets/Sets the caption on the button

Command Button

To create a command button you need to add a command name to the button. You add a command name to the button with the CommandName property and a command argument with the CommandArgument property. Both these properties can hold text which can be recovered in code.

Sample Code1

Drag a Button onto the form from the toolbox and set it's text as ClickMe. When you click the button it changes it's text from ClickMe to "You clicked Me". The code for that looks like this:

Private Sub Button1_Click(ByVal sender As System.Object,_ ByVal e As System.EventArgs) Handles Button1.Click Button1.Text = "You clicked me" End Sub

Sample code to create a Command Button

Drag two TextBoxes and Buttons from the toolbox. Select Button one and in it's properties window set the CommandName property to Command1 and CommandArgument property to I am Command one. Repeat the same for Button two. When you click Button1, the CommandName of Button1 will be displayed in TextBox1 and CommandArgument of Button2 in TextBox2. To get those values we need to use the command event for the button and not the click event. The code for that looks like this:

Private Sub Button1_Command(ByVal sender As System.Object,_ ByVal e As System.Web.UI.WebControls.CommandEventArgs) Handles Button1.Command TextBox1.Text = e.CommandName End Sub Private Sub Button2_Command(ByVal sender As System.Object,_ ByVal e As System.Web.UI.WebControls.CommandEventArgs) Handles Button2.Command TextBox2.Text = e.CommandArgument End Sub

Live Code Demo

Sample 1