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Chapter 2: ColdFusion Functions
REFind
Returns the position of the first occurrence of a regular expression in a string starting
from the specified position. Returns 0 if no occurrences are found. This search is case
sensitive.
Returns the position and length of the first occurrence of a regular expression in a
string if the returnsubexpressions parameter is set to True. See the description of the
returnsubexpressions parameter and the "Usage" section for details.
See also Find, REFindNoCase, and REReplace.
Syntax
REFind( reg_expression , string [, start ]
[, returnsubexpressions ] )
reg_expression
Regular expression used for search. This regular expression can include POSIX-
specified character classes (for example, [[:alpha:]], [[:digit:]], [[:upper:]], and
[[:lower:]]).
string
String being searched.
start
Optional. Starting position for the search. Default is 1.
returnsubexpressions
Optional. A Boolean value indicating whether a substring is returned. If you set
this parameter to TRUE, the function returns a CFML structure composed of two
arrays containing the position and length of the first substring that matches the
criteria of the search. You can retrieve the position and length of the matching
subexpression by using the keys "pos" and "len." If there are no occurrences of the
regular expression, the "pos" and the "len" arrays each contain one element that
has a value of zero. If you set this parameter to FALSE, a scalar value is returned
indicating the position of the first occurrence of a regular expression. The default
value of this parameter is FALSE.
Usage
In order to find multiple instances of a substring, you must call REFind more than
once, each time with a different starting position. To determine the next starting
position for the function, use the returnsubexpressions parameter and add the value
returned in the position key to the value in the length key.
If you do not use parentheses in the regular expression, the returnsubexpressions
parameter returns single element arrays that denote the position and length of the first
match found in the string.
If you do use parentheses to denote subexpressions within the regular expression, the
returnsubexpressions parameter returns the position and length of the first match of
the regular expression in the first element of the respective arrays; the position and
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