The unary not is a unary operator that logically negates the result of the expression.
!(expression)
If the negation of an operand (for example, when an operand is false) is true, the value true is returned. On the contrary, if the negation of an operand (for example, when an operand is true) is false, the value false is returned.
The unary operator is placed before an operand, linking from the right to the left.
bool IsLastDialog;
IsLastDialog = false;
if (!IsLastDialog)
AIT_LogMessage("Installable Software Extracting... is opened.");
else
AIT_LogMessage("Installable Software Extracting... is not opened.");
endif;