The following Basic syntax is supported:
- sub .. end and function .. end declarations
- byref and dim directives
- if .. then .. else .. end constructor
- for .. to .. step .. next constructor
- do .. while .. loop and do .. loop .. while constructors
- do .. until .. loop and do .. loop .. until constructors
- ^ , * , / , and , + , - , or , <> , >=, <= , = , > , < , div , mod , xor , shl , shr operators
- try .. except and try .. finally blocks
- try .. catch .. end try and try .. finally .. end try blocks
- select case .. end select constructor
- array constructors (x:=[ 1, 2, 3 ];)
- exit statement
- access to object properties and methods ( ObjectName.SubObject.Property )
2. Script structure
A script structure is made of two major blocks: a) function and sub declarations and b) main block. Both are optional, but at least one should be present in the script. Some examples:
MyFunction = "Ok!"
Like in normal basic, statements in a single line can be separated by ":" character.
Identifier names in the script (variable names, function and procedure names, etc.) follow the most common rules in basic: should begin with a character (a..z or A..Z), or '_', and can be followed by alphanumeric chars or '_' char. Cannot contain any other character os spaces.
4.2.4 Assign statements
Assign statements (assign a value or expression result to a variable or object property) are built using "=". Examples:
MyVar = 2
Button.Caption = "This " + "is ok."
5. New statement
The script provides the "new" statement for Basic syntax. Since you don't provide the method name in this statement, scripter studio looks for a method named "Create" in the specified class. If the method doesn't exist, the statement fails. Example:
MyLabel = new TLabel(Form1)
MyFont = new TFont
In the above examples, a method named "Create" for TLabel and TFont class will be called. The method must be registered. If the method receives parameters, you can pass the parameters in parenthesis, like the TLabel example above.
6. Character strings
Strings (sequence of characters) are declared in basic using the double quote (") character. Some
A = "This is a text"
Str = "Text "+"concat"
Comments can be inserted into the script. You can use ' chars or REM. Comment will finish at the end of the line. Examples:
' This is a comment before ShowMessage
REM This is another comment
' And this is a comment
' with two lines
ShowMessage("End of okays")
There is no need to declare variable types in the script. Thus, you declare variable just using DIM directive and its name. There is no need to declare variables if when the property OptionExplicit is set to false. In this case, variables are implicit declared. If you want to have more control over the script, set the OptionExplicit property to true. This will raise a compile error if the variable is used but not declared in the script. Examples:
S = "Hello world!"
A = 0
A = A+1
Note that if the script property OptionExplicit is set to false, then variable declarations are not necessary for any of the scripts above.
You can also declare global variables as private or public using the following syntax:
B = 0
A = B + 1
Variable declared with DIM statement are public by default. Private variables are not accessible from other scripts.
Variables can be default initialized with the following syntax
DIM A = "Hello world"
DIM B As Integer = 5
Strings, arrays and array properties can be indexed using "[" and "]" chars. For example, if Str is a string variable, the expression Str returns the third character in the string denoted by Str, while Str[I+ 1] returns the character immediately after the one indexed by I. More examples:
MyChar = MyStr
MyStr = "A"
MyArray[1,2] = 1530
Lines.Strings = "Some text"
Script support array constructors and support to variant arrays. To construct an array, use "[" and "]" chars. You can construct multi-index array nesting array constructors. You can then access arrays using indexes. If the array is multi-index, separate indexes using ",".
If the variable is a variant array, the script automatically supports indexing in that variable. A variable is a variant array is it was assigned using an array constructor, if it is a direct reference to a Delphi variable which is a variant array (see Delphi integration later) or if it was created using the VarArrayCreate procedure.
Arrays in script are 0-based index. Some examples:
NewArray = [ 2,4,6,8 ]
Num = NewArray //Num receives "4"
MultiArray = [ ["green","red","blue"] , ["apple","orange","lemon"] ]
Str = MultiArray[0,2] //Str receives 'blue'
MultiArray[1,1] = "new orange"
11. If statements
There are two forms of if statement: if...then..end if and the if...then...else..end if. Like normal basic, if the if expression is true, the statements are executed. If there is else part and expression is false, statements after else are executed. Examples:
IF J <> 0 THEN Result = I/J END IF
IF J = 0 THEN Exit ELSE Result = I/J END IF
IF J <> 0 THEN
Result = I/J
Count = Count + 1
Done = True
If the IF statement is in a single line, you don't need to finish it with END IF:
IF J <> 0 THEN Result = I/J
IF J = 0 THEN Exit ELSE Result = I/J
12. while statements
A while statement is used to repeat statements, while a control condition (expression) is evaluated as true. The control condition is evaluated before the statements. Hence, if the control condition is false at the first iteration, the statement sequence is never executed. The while statement executes its constituent statement repeatedly, testing expression before each iteration. As long as expression returns True, execution continues. Examples:
WHILE (Data[I] <> X) I = I + 1 END WHILE
WHILE (I > 0)
IF Odd(I) THEN Z = Z * X END IF
X = Sqr(X)
WHILE (not Eof(InputFile))
13. loop statements
The script supports loop statements. The possible syntax are:
DO WHILE expr statements LOOP
DO UNTIL expr statements LOOP
DO statements LOOP WHILE expr
DO statement LOOP UNTIL expr
The statements will be executed WHILE expr is true, or UNTIL expr is true. if expr is before the statements, then the control condition will be tested before iteration. Otherwise, the control condition will be tested after iteration. Examples:
K = I mod J
I = J
J = K
LOOP UNTIL J = 0
DO UNTIL I >= 0
Write("Enter a value (0..9): ")
K = I mod J
I = J
J = K
LOOP WHILE J <> 0
DO WHILE I < 0
Write("Enter a value (0..9): ")
14. for statements
The script supports for statements with the following syntax: FOR counter = initialValue TO finalValue STEP stepValue statements NEXT. The for statement sets the counter to initialValue, repeats execution of statement until "next" and increments the value of the counter by stepValue, until the counter reaches finalValue.
Step part is optional, and if omitted stepValue is considered 1. Examples:
FOR c = 1 TO 10 STEP 2
a = a + c
FOR I = a TO b
j = i ^ 2
sum = sum + j
15. select case statements
The script supports select case statements with the following syntax:
SELECT CASE selectorExpression
If the selectorExpression matches the result of one of caseexprn expressions, the respective statements will be executed. Otherwise, the else statement will be executed. The Else part of the case statement is optional. Example:
SELECT CASE uppercase(Fruit)
CASE "lime" ShowMessage("green")
CASE "apple" ShowMessage("red")
16. function and sub declaration
Declaration of functions and subs are similar to basic. In functions to return function values, use implicit declared variable which has the same name of the function, or use the Return statement. Parameters by reference can also be used, using BYREF directive. Some examples:
TodayAsString = DateToStr(Date)
IF A>B THEN
MAX = A
MAX = B
SUB SwapValues(BYREF A, B)
TEMP = A
A = B
B = TEMP
You can also declare subs and functions as private or public using the following syntax:
PRIVATE SUB Hello
PUBLIC FUNCTION Hello
Subs and functions are public by default. Private subs and functions are not accessible from other scripts.
You can use Return statement to exit subs and functions. For functions, you can also return a valid
'This line will be never reached