Hi, On Apr 13, 2:42 pm, kangax <[email protected]> wrote: > We've been getting these requests in the past. Take a look at, for > example: > <URL:http://groups.google.com/group/prototype-core/browse_thread/thread/8e...> > > I still think that it's not a trivial solution (for the reasons > outlined in the post linked above)...
"Oh my sweet Lord in heaven!" he exclaimed, after reading the stackoverflow answer linked from the above and seeing all of the myriad inconsistencies. Blech. That's useful to know, thanks. jQuery seems to go with the collect-all-text-nodes answer, completely ignoring innerText and textContext, presumably for these very reasons. It also fails to strip the content of script tags (like FF's textContext does), which seems odd (doesn't look very optimized, either, but perhaps it's fast enough without). But I would argue that these reasons are exactly why Prototype should have this feature. This is Prototype's raison d'etre, smoothing out various browser differences (and outright insanities, such as including script contents!). I coded up a simple text node gatherer[1] that omits the contents of script elements, and the performance isn't bad at all. Even using the slowest major browser, it happily gave me the 12k of text content in a moderately-complex page (various menus and controls, plus a 580-row 3- column table containing links) in about a third of a second on my little Atom-class netbook. I created a bookmarklet[2] of it that reports character count, time, and such and ran it against a large, complex document (the current all- in-one-page HTML5 specification[3]) using Chrome, which gave me all 2,090,693 characters spread across 86,018 elements (I didn't count all nodes, just elements) in just under two seconds (again on the netbook). Firefox did the same in just under three seconds, and IE7 (after taking several *minutes* -- and several script errors -- just to load the document) ran the bookmarklet in 12.5 seconds. Pretty decent for IE. :-) The character counts were identical between Chrome and Firefox; IE saw slightly fewer characters (1,891,293) and elements (85,972), but that could have been down to the script errors. Firefox reported one fewer element than Chrome. I haven't particularly tested or optimized that code, it's just a starting point. It builds things up in an array and uses #join at the end, which is probably slower for small tasks than jQuery's approach (string concatenation), but probably faster for large tasks (like the HTML spec). I say "probably" in each case because I haven't tested, and I've learned not to make performance assertions without data. :-) [1] http://pastie.org/917566 (also quoted inline below) [2] http://pastie.org/917567 [3] http://www.w3.org/TR/html5/Overview.html (warning: *LARGE* document) Code from [1] pasted inline: * * * * Element.addMethods((function() { /** * Element.textValue() -> String * * Gets the text within the element, ignoring any tags; e.g., returns the sum of all of the * text nodes. Omits the text nodes within `script` elements. **/ function textValue(element) { if (!(element = $(element))) return; var collector = []; textValueCollector(element, collector); return collector.join(""); } function textValueCollector(element, collector) { var node; for (node = element.firstChild; node; node = node.nextSibling) { switch (node.nodeType) { case 3: // text case 4: // cdata collector.push(node.nodeValue); break; case 8: // comment break; case 1: // element if (node.tagName == 'SCRIPT') { break; } // FALL THROUGH TO DEFAULT default: // Descend textValueCollector(node, collector); break; } } } return {textValue: textValue}; })()); * * * * -- T.J. :-) On Apr 13, 2:42 pm, kangax <[email protected]> wrote: > We've been getting these requests in the past. Take a look at, for > example: > <URL:http://groups.google.com/group/prototype-core/browse_thread/thread/8e...> > > I still think that it's not a trivial solution (for the reasons > outlined in the post linked above) and so is best handled by a > standalone plugin. And using context-unaware `stripTags` on something > like HTML is usually asking for trouble :) (imagine what stripTags > would do to a string like this — "foo bar <script>function wrap(html) > { return 'div' + html + '</div>'}</script> baz"; and then there are > other elements with CDATA content model, like STYLE) > > -- > kangax > > On Apr 13, 8:20 am, "T.J. Crowder" <[email protected]> wrote: > > > > > On Apr 13, 10:39 am, Eric <[email protected]> wrote: > > > > wouldn't it be wiser to check for the native method once and use it? > > > Probably. I'd also check for innerText (in fact, I'd check for that > > first), since it's supported by IE, WebKit (so Chrome, Safari), and > > Opera; only Mozilla holds out. textContent is supported by all of them > > except IE. So: > > > Element.addMethods((function() { > > > return { > > /** > > * Element.text() -> String > > * > > * Gets the text within the element, ignoring any tags > > (essentially the sum of all of the > > * text nodes within). > > **/ > > text: (function() { > > var element, testvalue; > > > element = document.createElement("span"); > > element.innerHTML = testvalue = "foo"; > > if (text_fromInnerText(element) == testvalue) { > > return text_fromInnerText; > > } > > if (text_fromTextContent(element) == testvalue) { > > return text_fromTextContent; > > } > > return text_fromStripping; > > })() > > }; > > > // Get the element's inner text via innerText if available (IE, > > WebKit, Opera, ...) > > function text_fromInnerText(element) { > > if (!(element = $(element))) return; > > return element.innerText; > > } > > > // Get the element's inner text via textContent if available > > (Gecko, WebKit, Opera, ...) > > function text_fromTextContent(element) { > > if (!(element = $(element))) return; > > return element.textContent; > > } > > > // Get the element's inner text by getting innerHTML and stripping > > tags (fallback) > > function text_fromStripping(element) { > > if (!(element = $(element))) return; > > return element.innerHTML.stripTags(); > > } > > > })()); > > > Do people think I should submit this to core? jQuery has an equivalent > > function, and I think I saw one in Closure as well. So it's not just > > the OP who wants to do this... > > > -- T.J. :-) > > > On Apr 13, 10:39 am, Eric <[email protected]> wrote: > > > > Oooops, gmail sent the message before I finished... :o) > > > > Here is the correct message (please ignore the previous one) > > > > On Apr 12, 7:04 pm, "T.J. Crowder" <[email protected]> wrote: > > > > > Element.addMethods({ > > > > text: function(element) { > > > > if (!(element = $(element))) return; > > > > return element.innerHTML.stripTags(); > > > > } > > > > }); > > > > wouldn't it be wiser to check for the native method once and use it? > > > > Something like (untested) > > > > Element.addMethods({ > > > text: ($$('BODY').first().textContent===undefined) > > > ? function(element) { if (!(element = $(element))) return; > > > return element.innerText; } > > > : function(element) { if (!(element = $(element))) return; > > > return element.textContent; } > > > > }); > > > > Eric > > > > NB: I know, the testing condition is ugly... feel free to post a > > > better one :o) -- You received this message because you are subscribed to the Google Groups "Prototype & script.aculo.us" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. 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