JavaScript Examples Bible - UserWorks Technologies

Chapter 5 ✦ Body Text Objects (Chapter 19)
Example
Listing 19-11 implements two varieties of a text search-and-replace operation,
while showing you how to include extra parameters for case-sensitive and whole
word searches. Both approaches begin by creating a TextRange for the entire body,
but they immediately shift the starting point to the beginning of the DIV element
that contains the text to search.
One search-and-replace function prompts the user to accept or decline replacement
for each instance of a found string. The select() and scrollIntoView()
methods are invoked to help the user see what is about to be replaced. Notice that
even when the user declines to accept the replacement, the text range is collapsed
to the end of the found range so that the next search can begin after the previously
found text. Without the collapse() method, the search can get caught in an infinite
loop as it keeps finding the same text over and over (with no replacement
made). Because no counting is required, this search-and-replace operation is implemented
inside a while repeat loop.
The other search-and-replace function goes ahead and replaces every match and
then displays the number of replacements made. After the loop exits (because
there are no more matches), the loop counter is used to display the number of
replacements made.
Listing 19-11: Two Search and Replace Approaches
(with Undo)
TextRange.findText() Method
// global range var for use with Undo
var rng
// return findText() third parameter arguments
function getArgs(form) {
var isCaseSensitive = (form.caseSensitive.checked) ? 4 : 0
var isWholeWord = (form.wholeWord.checked) ? 2 : 0
return isCaseSensitive ^ isWholeWord
}
// prompted search and replace
function sAndR(form) {
var srchString = form.searchString.value
var replString = form.replaceString.value
if (srchString) {
var args = getArgs(form)
rng = document.body.createTextRange()
rng.moveToElementText(rights)
clearUndoBuffer()
while (rng.findText(srchString, 10000, args)) {
rng.select()
Continued
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TextRange.findText()