JavaScript Examples Bible - UserWorks Technologies

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JavaScript Examples Bible: The Essential Companion to JavaScript Bible
stringObject.replace()
RegExp Description
man Both case-sensitive and not
man\b Where “man” is at the end of a word
\bman Where “man” is at the start of a word
me*an Where zero or more “e” letters occur between “m” and “a”
.a. Where “a” is surrounded by any one character (including
space)
\sa\s Where “a” is surrounded by a space on both sides
z Where a “z” occurs (none in the default string)
In the scripts for Listing 34-3, if the string.match() method returns null, you
are informed politely, and the count field is emptied.
string.replace(regExpression, replaceString)
NN2 NN3 NN4 NN6 IE3/J1 IE3/J2 IE4 IE5 IE5.5
Compatibility ✓ ✓ ✓ ✓ ✓
Example
The page in Listing 34-4 lets you practice with the string.replace() and
string.search() methods and regular expressions in a friendly environment. The
source text is a five-line excerpt from Hamlet. You can enter the regular expression
to search for, and the replacement text as well. Note that the script completes the
job of creating the regular expression object, so that you can focus on the other
special characters used to define the matching string. All replacement activities act
globally, because the g parameter is automatically appended to any expression you
enter.
Default values in the fields replace the contraction ‘tis with “it is” after you click
the “Execute replace( )” button (see Figure 16-2). Notice that the backslash character
in front of the apostrophe of ‘tis (in the string assembled in mainString) makes
the apostophe a non-word boundary, and thus allows the \B’t regular expression
to find a match there. As described in the section on the string.search()
method, the button connected to that method returns the offset character number
of the matching string (or -1 if no match occurs).