Access Keys

An access key is an alphanumeric key — sometimes referred to as a mnemonic — that when used in combination with the ALT key navigates to and activates a control. The access key matches one of the characters in the text label of the control. For example, pressing ALT+O activates a control whose label is "Open" and whose assigned access key is "O". Typically, access keys are not case sensitive. The effect of activating a control depends on the type of control.

Assign access key characters to controls using the following guidelines (in order of choice):

1. The first letter of the label for the control, unless another letter provides a better mnemonic association.
2. A distinctive consonant in the label.
3. A vowel in the label.

Avoid assigning a character where the visual indication of the access key cannot be distinguished from the character. Also, avoid using a character normally assigned to a common function. For example, when you include an Apply button, reserve the "A" — or its localized equivalent — as the access key for that button. In addition, do not assign access keys to the OK and Cancel commands when they map to the ENTER and ESC keys, respectively.

Nonunique access key assignments within the same scope access the first control. Depending on the control, if the user presses the access key a second time, it may or may not access another control with the same assignment. Therefore, define an access key to be unique within the scope of its interaction — that is, the area in which the control exists and to which keyboard input is currently being directed.

Controls without explicit labels can use static text controls to create labels with assigned access keys. Software that supports a nonroman writing system (such as Kanji), but that runs on a standard keyboard, can prefix each control label with an alphabetic (roman) character as its access key.

Note
For more information about static text controls, see Chapter 7, "Menus, Controls, and Toolbars."