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{{refimproveMore citations needed|date =November 2006}}

'''CFScript''' is an extension of [[ColdFusion Markup Language|CFML]] on the ColdFusion platform. CFScript resembles [[JavaScript]]. Some ColdFusion [[Software Developers|developers]] prefer it since it has less visual and typographical overhead than ordinary CFML;.{{Clarify|reason=|date=March only the actual changes are represented in the code (whereas normal CFML would involve CFSET tags at every line).2020}}

== Usage ==

Unless it is within a pure script-based ColdFusion Component, all CFScript code must be contained within a CFScript tag pair as follows:

<syntaxhighlight lang="cfm">

<cfscript>

xParam = 115;

yParam = 200;

color = 'FFCC99';

</cfscript>

</syntaxhighlight>

A simple example of a [[Subroutine|function]]:

All CFScript code must be contained within a CFScript tag pair, as follows:

<syntaxhighlight lang="cfm">

<pre>

<cfscript>

function Sum(a, b) {

xParam = 115;

yParamvar sum = 200a + b;

colorreturn = 'FFCC99'sum;

}

</cfscript>

</syntaxhighlight>

</pre>

A simple example of a component in CFScript, containing two functions:

While many ColdFusion tags have exact CFScript analogies, there are quite a few tags that do not. These include both complex tags that would be difficult to duplicate and simple tags that are easy to imitate (using ColdFusion UDF's):

<syntaxhighlight lang="javascript">

component {

public void function foo() {

WriteOutput("Method foo() called<br/>");

}

public function getString() {

Complex:

var x = "hello";

<pre>

return x;

<cfquery>

}

<cffile>

}

<cfdirectory>

</syntaxhighlight>

</pre>

ColdFusion 11, [[Railo]] 4.1+, and [[Lucee]] 4.5+ both do their best to fully support cf tags in CFScript.

Simple:

While there may not be direct substitutions for all tags, it is often still possible to achieve the results of a tag in script, but via a different syntax. For example, this is how to get a query into a variable in CFSCRIPT without writing a [[User-defined function|UDF]]:

<pre>

<syntaxhighlight lang="cfm">

<cfdump>

<cfthrow>

</pre>

While there may not be direct substitutions for all tags, it is often still possible to achieve the results of a tag in script, but via a different syntax. For example this is how to get a query into a variable in CFSCRIPT without writing a UDF:

<pre>

<cfscript>

qGetData = new Query();

qGetData .setDataSource('#APPLICATIONApplication.datasource#');

qGetData .setSQL('SELECT column1, column2 FROM table WHERE 1');

qDateResult = qGetData .Execute().getResult();

</cfscript>

</syntaxhighlight>

</pre>

== Syntax ==

Since ColdfusionColdFusion 8, cfscriptCFScript has supported [[Syntax (programming languages)|syntax]] abbreviations that are common in many other programming languages, such as "++", "<=" and "+=".<ref>Nadel,{{Cite Ben. httpweb|url=https://www.bennadel.com/blog/741-Learninglearning-ColdFusioncoldfusion-8-Allall-Hailhail-Thethe-Newnew-Operatoroperator.htm|title=Learning ColdFusion 8: All Hail The New ++ Operator|last=Nadel|first=Ben|date=May 31, 2007|website=|archive-url=|archive-date=|access-date=}}</ref>

=== Arithmetic operators ===

==References==

{| class="wikitable"

|-

! Operator !! Description

|-

| + - * / || Basic arithmetic: Addition, subtraction, multiplication, and division.

In division, the right operand cannot be zero.

|-

| ++ -- || Increment and decrement. Increase or decrease the variable by one.

These operators can be used for pre-incrementing or decrementing (as in x = ++ i), where the variable is changed before it is used in the expression. They can also be used for post-incrementing or decrementing (as in x = i++), where the value is changed after it is used in the expression. If the value of the variable i is initially 7, for example, the value of x in x = ++i is 8 after expression evaluation, but in x=i++, the value of x is 7. In both cases, the value of i becomes 8.

These operators cannot be used with expressions that involve functions, as in f().a++. Also, you can use an expression such as -++x, but ---x and +++x cause errors, because their meanings are ambiguous. You can use parentheses to group the operators, as in -(--x) or +(++x), however.

|-

| += -= *= /= %= || Compound assignment operators. The variable on the right is used as both an element in the expression and the result variable. Thus, the expression a += b is equivalent to a = a +b.

An expression can have only one compound assignment operator.

|-

| + - || Unary arithmetic: Set the sign of a number.

|-

| MOD or % || Modulus: Return the remainder after a number is divided by a divisor. The result has the same sign as the divisor. The value to the right of the operator should be an integer; using a non-numeric value causes an error, and if you specify a real number, ColdFusion ignores the fractional part (for example, 11 MOD 4.7 is 3).

|-

| \|| Integer division: Divide an integer by another integer. The result is also an integer; for example, 9\4 is 2. The right operand cannot be zero

|-

| ^|| Exponentiation: Return the result of a number raised to a power (exponent). Use the caret character (^) to separate the number from the power; for example, 2^3 is 8. Real and negative numbers are allowed for both the base and the exponent. However, any expression that equates to an imaginary number, such -1^.5 results in the string "-1.#IND. ColdFusion does not support imaginary or complex numbers.

|}

=== Comments ===

CFScript has two forms of comments: single line and multiline.

<syntaxhighlight lang="javascript">

// This is a single-line comment.

// This is a second single-line comment.

</syntaxhighlight>

<syntaxhighlight lang="javascript">

/* This is a multiline comment.

You do not need to start each line with a comment indicator.

This line is the last line in the comment. */

</syntaxhighlight>

=== Try / catch ===

<syntaxhighlight lang="javascript">

try {

throw(message="Oops", detail="xyz");

} catch (any e) {

WriteOutput("Error: " & e.message);

rethrow;

} finally {

WriteOutput("I run even if no error");

}

</syntaxhighlight>

=== Switch statement ===

<syntaxhighlight lang="javascript">

switch (car) {

case "Nissan":

WriteOutput("I own a Nissan");

break;

case "Toyota":

WriteOutput("I own a Toyota");

break;

default:

WriteOutput("I'm exotic");

}

</syntaxhighlight>

=== Looping ===

==== For loop ====

<syntaxhighlight lang="javascript">

for (i=1; i <= ArrayLen(array); i=i+1) {

WriteOutput(array[i]);

}

</syntaxhighlight>

==== FOR IN Loop ====

<syntaxhighlight lang="javascript">

struct = StructNew();

struct.one = "1";

struct.two = "2";

for (key in struct) {

WriteOutput(key);

}

//OUTPUTS onetwo

</syntaxhighlight>

==== While loop ====

<syntaxhighlight lang="javascript">

x = 0;

while (x < 5) {

x = x + 1;

WriteOutput(x);

}

// Outputs: 12345

</syntaxhighlight>

==== Do / while loop ====

<syntaxhighlight lang="javascript">

x = 0;

do {

x = x + 1;

WriteOutput(x);

} while (x <= 0);

// Outputs: 1

</syntaxhighlight>

==== Looping over an array ====

<syntaxhighlight lang="javascript">

for (item in array) {

doSomething(item);

}

</syntaxhighlight>

== Differences from JavaScript ==

Although CFScript and JavaScript are similar, they have several key differences. The following list identifies CFScript features that differ from JavaScript:

* CFScript uses ColdFusion [[Expression (computer science)|expression]], which are not a superset or a subset of JavaScript expressions. In particular, ColdFusion expressions do not support [[Bitwise operation|bitwise operators]], and the ColdFusion MOD or % operator operates differently from the corresponding JavaScript % operator: In ColdFusion, the operator does integer arithmetic and ignores fractional parts. ColdFusion expressions also support the EQV, IMP, CONTAINS, and DOES NOT CONTAIN operators that are not supported in JavaScript.

*[[Variable declaration|Variable declarations]] (var keyword) are only used in user-defined functions and threads.

* CFScript is not case sensitive.

* All statements end with a semicolon, and line breaks in the code are ignored.

* Assignments are statements, not expressions, and therefore cannot be used in situations that require evaluating the assignment operation.

* JavaScript objects, such as <code>window</code> and <code>document</code>, are not available.

* Only the ColdFusion server processes CFScript. There is no client-side CFScript.

== References ==

{{Reflist}}

== External Linkslinks ==

* [http://help.adobe.com/en_US/ColdFusion/9.0/Developing/WSc3ff6d0ea77859461172e0811cbec22c24-7feb.html Extending ColdFusion Pages with CFML Scripting - Adobe]

* [https://helpx.adobe.com/coldfusion/developing-applications/the-cfml-programming-language/extending-coldfusion-pages-with-cfml-scripting.html]

{{DEFAULTSORT:Cfscript}}

[[Category:CFML programming language]]

[[Category:Scripting languages]]

{{Compu-lang-stub}}