Type: Boolean
Availability: Read or write at any time
The controlBox property of the Form class specifies whether a Control-Menu icon is displayed on a form at run time. (The Control-Menu icon at the top left of a form takes the icon image of the form. For example, the Control‑Menu icon for JADE development environment forms is the JADE logo and in Microsoft Word it is displayed as the Word icon image.)
The controlBox property settings are listed in the following table.
| Value | Description |
|---|---|
| true | Displays the Control-Menu icon (the default). |
| false | Removes the Control-Menu icon. |
Setting the controlBox property to true causes a form with the borderStyle property set to BorderStyle_None (0) to change to a borderStyle value of BorderStyle_Single (1). Additionally, setting the controlBox property to true causes the form to be displayed with a caption box if it did not have one. The setting of this property after the window has been created is ignored when an MDI child form is maximized.
Both modal and non-modal windows can include a Control-Menu icon.
The commands available at run time depend on the settings for related properties. For example, setting the maxButton and minButton properties to false disables the Maximize and Minimize commands on the Control-Menu but the Move and Close commands remain available.
Without a Control-Menu icon on a form, the user has no way of closing a form. The form can be closed only when the unloadForm method is called from logic.