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Sign inForm.HelpButtonClicked 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 Help button is clicked.
public:
event System::ComponentModel::CancelEventHandler ^ HelpButtonClicked;[System.ComponentModel.Browsable(true)]
public event System.ComponentModel.CancelEventHandler HelpButtonClicked;[System.ComponentModel.Browsable(true)]
public event System.ComponentModel.CancelEventHandler? HelpButtonClicked;[<System.ComponentModel.Browsable(true)>]
member this.HelpButtonClicked : System.ComponentModel.CancelEventHandler Public Custom Event HelpButtonClicked As CancelEventHandler - Attributes
The following example demonstrates the use of this member. In the example, an event handler reports on the occurrence of the HelpButtonClicked event. This report helps you to learn when the event occurs and can assist you in debugging. To report on multiple events or on events that occur frequently, consider replacing MessageBox.Show with Console.WriteLine or appending the message to a multiline TextBox.
To run the example code, paste it into a project that contains an instance of type Form named Form1. Then ensure that the event handler is associated with the HelpButtonClicked event.
private void Form1_HelpButtonClicked(Object sender, CancelEventArgs e) {
System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "Cancel", e.Cancel );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "HelpButtonClicked Event" );
}
Private Sub Form1_HelpButtonClicked(sender as Object, e as CancelEventArgs) _
Handles Form1.HelpButtonClicked
Dim messageBoxVB as New System.Text.StringBuilder()
messageBoxVB.AppendFormat("{0} = {1}", "Cancel", e.Cancel)
messageBoxVB.AppendLine()
MessageBox.Show(messageBoxVB.ToString(),"HelpButtonClicked Event")
End Sub
The HelpButtonClicked event occurs when the Help button in the form's caption bar is clicked. The Help button is displayed when the HelpButton property is set to true. HelpButtonClicked can be canceled.
For more information about handling events, see Handling and Raising Events.
Applies to
| Product | Versions |
|---|---|
| .NET Framework | 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
| Windows Desktop | 3.0, 3.1, 5, 6, 7, 8, 9, 10 |