HTML and CSS Reference
In-Depth Information
EXPLANATION
1
A string is assigned to the variable, called
string
.
2
The
replace()
method will search for the pattern
Tommy Savage
. Because the
search side of the
replace()
method contains the pattern
Tommy
enclosed in paren-
theses and the pattern
Savage
enclosed in parentheses, each of these subpatterns
will be stored in
$1
and
$2
, respectively. A third pattern would be stored in
$3
and
a fourth pattern in
$4
, and so on. On the replacement side of the
replace()
method,
$2
and
$1
are replaced in the string, so that
Savage
is first, then a comma, and then
Tommy
. The first and last names have been reversed.
3
The new string is displayed. See Figure 17.36.
Figure 17.36
Output from Example 17.34.
EXAMPLE
17.35
<html>
<head><title>Capture and Replace</title></head>
<body>
<big>
<script type = "text/javascript">
1
var string="Tommy Savage:203-123-4444:12 Main St."
2
var newString=string.replace(/(\w+)\s(\w+)/, "$2, $1");
3 document.write(newString +"<br />");
</script>
</big>
</body>
</html>
EXPLANATION
1
A string is created to be used by the
replace()
method in line 2.
2
The
replace()
method searches for one or more alphanumeric word characters,
followed by a single space, and another set of alphanumeric word characters. The
word characters are enclosed in parentheses, and thus captured.
$1
will contain
Tommy
, and
$2
will contain
Savage
. On the replacement side,
$1
and
$2
are re-
versed. After the replacement is made, a new string is created.
3
The value of
newString
shows that the capturing and the substitution occurred
successfully, leaving the remainder of the string as it was. See Figure 17.37.
