Using CFScript statements

The following sections describe how to use these CFScript statements:

Using assignment statements and functions

CFScript assignment statements are the equivalent of the cfset tag. These statements have the following form:

lval = expression;

lval is any ColdFusion variable reference; for example:

x = "positive";
y = x; 
a[3]=5; 
structure.member=10;
ArrayCopy=myArray;

You can use ColdFusion function calls, including UDFs, directly in CFScript. For example, the following line is a valid CFScript statement:

StructInsert(employee,"lastname",FORM.lastname);

Using conditional processing statements

CFScript includes the following conditional processing statements:

if and else statements, which serve the same purpose as the cfif, cfelseif, and cfelse tags
switch, case, and default statements, which are the equivalents of the cfswitch, cfcase, and cfdefaultcase tags

Using if and else statements

The if and else statements have the following syntax:

if(expr) statement [else statement]

In its simplest form, an if statement looks like this:

if(value EQ 2700)
   message = "You've reached the maximum";

A simple if-else statement looks like the following:

if(score GT 1)
   result = "positive";
else
   result = "negative";

CFScript does not include an elseif statement. However, you can use an if statement immediately after an else statement to create the equivalent of a cfelseif tag, as the following example shows:

if(score GT 1)
   result = "positive";
else if(score EQ 0)
   result = "zero";
else
   result = "negative";

As with all conditional processing statements, you can use curly braces to enclose multiple statements for each condition, as follows:

if(score GT 1) {
   result = "positive";
   message = "The result was positive.";
   }
else {
   result = "negative";
   message = "The result was negative.";
   }

Note: Often, you can make your code clearer by using braces even where they are not required.

Using switch and case statements

The switch statement and its dependent case and default statements have the following syntax:

switch (expression) {
   case constant: [case constant:]... statement(s) break; 
   [case constant: [case constant:]... statement(s) break;]... 
   [default: statement(s)] }

Use the following rules and recommendations for switch statements:

You cannot mix Boolean and numeric constant values in a switch statement.
Each constant value must be a constant (that is, not a variable, a function, or other expression).
Multiple case constant: statements can precede the statement or statements to execute if any of the cases are true. This lets you specify several matches for one code block.
No two constant values can be the same.
The statements following the colon in a case statement block do not have to be in braces. If a constant value equals the switch expression, ColdFusion executes all statements through the break statement.
The break statement at the end of the case statement tells ColdFusion to exit the switch statement. ColdFusion does not generate an error message if you omit a break statement. However, if you omit it, ColdFusion executes all the statements in the following case statement, even if that case is false. In nearly all circumstances, this is not what you want to do.
You can have only one default statement in a switch statement block. ColdFusion executes the statements in the default block if none of the case statement constants equals the expression value.
The default statement does not have to follow all switch statements, but it is good programming practice to do so. If any switch statements follow the default statement you must end the default block code with a break statement.
The default statement is not required. However, you should use one if the case constants do not include all possible values of the expression.
The default statement does not have to follow all the case statements; however, it is good programming practice to put it there.

The following switch statement takes the value of a name variable:

If the name is John or Robert, it sets both the male variable and the found variable to True.
If the name is Mary, it sets the male variable to False and the found variable to True.
Otherwise, it sets the found variable to False.

switch(name) {
   case "John": case "Robert":
      male=True;
      found=True;
      break;
   case "Mary":
      male=False;
      found=True;
      break;
   default:
      found=False;
} //end switch

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