An application sends an EM_SETPASSWORDCHAR message to set or remove a password character displayed in an edit control when the user enters text. When a password character is set, that character is displayed for each character the user types in.
This message sets the character displayed in an edit control created with the ES_PASSWORD style. The default display character is an asterisk (*).
The EM_SETPASSWORDCHAR message may be used as either a wide-character message (where text arguments must use Unicode) or an ANSI message (where text arguments must use characters from the Windows 3.x character set installed).
wParam
Specifies the character to be displayed in place of the character typed by the user. If wParam is zero, the actual characters typed by the user are displayed.
lParam
This parameter is not used.
If the edit control is created with the ES_PASSWORD style, the default password character is set to an asterisk (*).