Okay. I have a really rough, unoptimized version of what I want. The
IE part is pretty simple, since it can move the selection boundary
range around. The Mozilla part is a bit more of a hack: I get the
full text of the node that the selection resides in, then based on the
selection offset within the node, I chop up the text around it to
determine the words just before and after the selected word. It
doesn't work quite perfectly, but it's close. It doesn't work with
Safari but I've tested it succesfully with Firefox (Mac) and IE 6
(Windows). (Safari has some weird text range issues...?!?)
Below is the code for an entire HTML page. Hopefully the word wrap
won't kill it. I freely admit it is an ugly, unoptimized hack thrown
together as a proof of concept, so you're welcome to clean it up, fix
bugs, add features, etc.
<html>
<head>
<title>Framglubble the Zartbox: getting selection context via
JavaScript</title>
<script language="javascript">
// Original author: Dekortage @ a server called Gmail.com
// You're free to copy this but leave the "Original author" line
intact.
//
// This deliberately returns a "null" value if it determines that the
previous
// or next word is separated from the selected word by a comma or
period.
// determine browsers
var isIE = document.all;
var isN6 = document.getElementById && !document.all;
var isN4 = document.layers;
var detect = navigator.userAgent.toLowerCase();
var isSafari = ( detect.indexOf("safari") 0 );
function trim(x) { return x.replace(/^\s*|\s*$/g,''); }
function moreInfo() {
if (!isIE) {
var t = window.getSelection(); // selected text
tx = t+"";
preWord = null;
postWord = null;
if (!isSafari) { // Safari does not work with this
origNode = t.anchorNode;
orig = origNode.textContent + "";
// get previous word
preTxt = orig.slice(0,t.anchorOffset);
preArray = preTxt.split(" ");
preCount = preArray.length;
while ((preWord == null) && (preCount >= 0)) {
preCount -= 1;
if ((preArray[preCount] != null) && (preArray[preCount] != "") &&
(preArray[preCount] != " ")) {
preWord = preArray[preCount];
if ((preWord.charAt(preWord.length-1) == ",")) preWord = null;
}
}
// get next word
postTxt = orig.slice((t.anchorOffset + tx.length + 1));
postArray = postTxt.split(" ");
if ((postArray[0] != ".") && (postArray[0] != ",") &&
(postArray[0] != "--") && (postArray[0] != "") &&
(postArray[0] != " ")) { // if not end of sentence
postWord = postArray[0];
}
}
showWords(tx,preWord,postWord);
} else if (document.selection && document.selection.createRange) {
var t = document.selection.createRange(); // selected text
if ((document.selection.type == 'Text') && (t.text '')) {
tx = trim(t.text);
t.moveStart("word",-1); // not sure why t.move() alone wouldn't work
t.moveEnd("word",-1);
preWord = trim(t.text);
if ((preWord == ",") || (preWord == ".")) {
preWord = null;
}
t.moveEnd("word",2);
t.moveStart("word",2);
postWord = trim(t.text);
if ((postWord == ",") || (postWord == ".")) {
postWord = null;
}
// need to fix this to work with hyphenated words
document.selection.empty();
showWords(tx,preWord,postWord);
}
}
}
function showWords(t,a,z) { window.alert("Sequence: "+a+","+t
+","+z); }
if (isIE) document.ondblclick=moreInfo;
</script>
</head>
<body ondblclick="if (!isIE) moreInfo()" style="font-size: 24px;
margin: 24px;">
<p>If you need to framglubble the zartbox, then you should buy the red
widget. Otherwise you can buy the blue widget and save some money.</p>
<p>(double-click on a word to see its context)</p>
</body>
</html>
