A control structure used to cause a script to perform a specified action if a stated condition is true. Syntax 1 uses a single-line format, and Syntax 2 uses a multiline format.
Syntax 1 (the single-line format):
IF condition THEN action1 {ELSE action2}
Parameter |
Description |
---|---|
condition |
The condition you want to test. |
action1 |
The action you want performed if the condition is true. The action must be a single statement on the same line as the rest of the IF statement. |
action2 (optional) |
The action you want performed if the condition is false. The action must be a single statement on the same line as the rest of the IF statement. |
Syntax 2 (the multiline format):
IF condition1 THEN action1 { ELSEIF condition2 THEN action2 . . . } { ELSE action3 } END IF
Parameter |
Description |
---|---|
condition1 |
The first condition you want to test. |
action1 |
The action you want performed if condition1 is true. The action can be a statement or multiple statements that are separated by semicolons or placed on separate lines. At least one action is required. |
condition2 (optional) |
The condition you want to test if condition1 is false. You can have multiple ELSEIF...THEN statements in an IF...THEN control structure. |
action2 |
The action you want performed if condition2 is true. The action can be a statement or multiple statements that are separated by semicolons or placed on separate lines. |
action3 (optional) |
The action you want performed if none of the preceding conditions is true. The action can be a statement or multiple statements that are separated by semicolons or placed on separate lines. |
You can use continuation characters to place the single-line format on more than one physical line in the script.
You must end a multiline IF...THEN control structure with END IF (which is two words).
Example 1 This single-line IF...THEN statement opens window w_first if Num is equal to 1; otherwise, w_rest is opened:
IF Num = 1 THEN Open(w_first) ELSE Open(w_rest)
Example 2 This single-line IF...THEN statement displays a message if the value in the SingleLineEdit sle_State is “TX”. It uses the continuation character to continue the single-line statement across two physical lines in the script:
IF sle_State.text="TX" THEN & MessageBox("Hello","Tex")
Example 3 This multiline IF...THEN compares the horizontal positions of windows w_first and w_second. If w_first is to the right of w_second, w_first is moved to the left side of the screen:
IF w_first.X > w_second.X THEN w_first.X = 0 END IF
Example 4 This multiline IF...THEN causes the application to:
Beep twice if X equals Y
Display the Parts list box and highlight item 5 if X equals Z
Display the Choose list box if X is blank
Hide the Empty button and display the Full button if none of the above conditions is true
IF X=Y THEN Beep(2) ELSEIF X=Z THEN Show (lb_parts); lb_parts.SetState(5,TRUE) ELSEIF X=" " THEN Show (lb_choose) ELSE Hide(cb_empty) Show(cb_full) END IF