The bu_UA global object is an instance of burst.web.UserAgent.
An instance has these member attributes which describe the browser:
For a good discussion, see http://www.xs4all.nl/~ppk/js/detect.html
A good list of useragent strings in the wild is http://www.xwolf.de/browserplaza/appnames.shtml An older larger list is: http://www.browserlist.browser.org/browser_mappings_list_big.html
For Netscape agent strings, see:
You generally do not want to have explicit tests for particular browser makes/versions in your code, as you'll inevitably have false positives and false negatives, and future maintainers will not know what you are really testing for.
Object detection works in some cases, but not always: it is not sufficient for circumstances where objects or methods exist, but there are crippling defects in their implementation. For those cases, something more advanced is needed.
Ideally, we would have automatic "bug detection" when "object detection" is insufficient. This could be done as a sort of lazy "autoconf" that kicks in the first time a feature is queried for while running; thereafter the answer would be cached.
If it didn't have so many technology dependencies, some variant of the W3 DOM2 unit tests could be used ( http://www.w3.org/2002/11/DOM-Level-2-HTML-Results/ ).
Our own browser_bugs.html test page (in this release) has a few tests as well.
For now however, we hardcode the answers; we do not determine the correct answer at run time. That is, the implementation of functions like Boolean bug_iframe_display_none() returns an answer based on browser make and version.
We distinguish between "bugs" and "features":
Generally speaking, a "bug" should be associated with a "less than or equal" test on particular browser brands and versions, indicating when it was fixed by.
A "feature" should be associated with a "greater than or equal" test on particular browser brands and versions, indicating when it started being available.
We have functions such as bug_iframe_display_none() for bugs, and can_iframe_onload_dyn() for features.
Public Member Functions | |
| Boolean | is_family_ie () |
| convenience for this.family_ == BU_UA_FAMILY_IE | |
| Boolean | bug_set_style_attribute () |
| true if the UA is unable to set the value of a 'style' attribute when the attribute name is a String. | |
| Boolean | bug_create_iframe () |
| true if the UA is unable to create an 'iframe' with document.createElement | |
| Boolean | bug_iframe_delayed_create () |
| true if a created iframe has no window until after a setTimeout or alert | |
| Boolean | bug_iframe_display_none () |
| true if the UA fails to process an iframe that has "display: none" | |
| Boolean | bug_iframe_relative_url () |
| true if the UA fails to treat links in a dynamically created iframe's contents relative to its parent (the src value of the iframe element, itself relativized to its window). | |
| Boolean | bug_ie_attributes () |
| true if Node.attributes is broken like ie. | |
| Boolean | can_iframe_onload_static () |
| True if the UA supports an onload attribute on an iframe element that is created through innerHTML or is statically already present in a document. | |
| Boolean | can_iframe_onload_dyn () |
| True if the UA supports an 'onload' attribute that is dynamically added to an iframe element through the DOM. | |
Static Public Attributes | |
| final String | BU_UA_FAMILY_IE = 'ie' |
| IE, excluding IE5 Mac. | |
| final String | BU_UA_FAMILY_IEMAC = 'iemac' |
| IE5 Mac. | |
| final String | BU_UA_FAMILY_OPERA = 'opera' |
| Opera. | |
| final String | BU_UA_FAMILY_KHTML = 'khtml' |
| Including konqueror, safari, atheos, and recent OmniWeb. | |
| final String | BU_UA_FAMILY_GECKO = 'gecko' |
| Including mozilla, netscape. | |
| final String | BU_UA_FAMILY_ICAB = 'icab' |
| icab. | |
| final String | BU_UA_FAMILY_ICE = 'ice' |
| InFix acquired Wind River AS which acquired ICEStorm from norwegian icesoft.no . | |
| final String | BU_UA_FAMILY_W3M = 'w3m' |
| See http://abe.nwr.jp/w3m/w3m-js-en.html for javascript. | |
| final String | BU_UA_FAMILY_UNKNOWN = 'unknown' |
| There is a navigator object, but not one we understand. | |
| final String | BU_UA_FAMILY_NONE = 'none' |
| There is not even a navigator object. | |
| final String | BU_UA_BRAND_KONQ = 'konqueror' |
| 'konqueror' | |
| final String | BU_UA_BRAND_SAFARI = 'safari' |
| 'safari' | |
| final String | BU_UA_BRAND_OPERA = 'opera' |
| 'opera' | |
| final String | BU_UA_BRAND_IE = 'ie' |
| 'ie' | |
| final String | BU_UA_BRAND_IEMAC = 'iemac' |
| 'iemac' | |
| final String | BU_UA_BRAND_NETSCAPE = 'netscape' |
| 'netscape' | |
| final String | BU_UA_BRAND_MOZILLA = 'mozilla' |
| 'mozilla' | |
| final String | BU_UA_BRAND_ICAB = 'icab' |
| 'icab' | |
| final String | BU_UA_BRAND_ICE = 'ice' |
| 'ice' | |
| final String | BU_UA_BRAND_W3M = 'w3m' |
| 'w3m' | |
| final String | BU_UA_BRAND_UNKNOWN = 'unknown' |
| 'unknown' | |
| final String | BU_UA_BRAND_NONE = 'none' |
| 'none' | |
| final String | BU_UA_OS_WIN = 'windows' |
| 'windows' | |
| final String | BU_UA_OS_MAC = 'mac' |
| 'mac' | |
| final String | BU_UA_OS_LINUX = 'linux' |
| 'linux' | |
| final String | BU_UA_OS_X11 = 'x11' |
| 'x11' | |
| final String | BU_UA_OS_UNKNOWN = 'unknown' |
| 'unknown' | |
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true if Node.attributes is broken like ie. |
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True if the UA supports an 'onload' attribute that is dynamically added to an iframe element through the DOM. The word "supports" here means that it would also need to be called after any dynamic location.replace. Also, the value set to the attribute is a Function, not a String. |
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True if the UA supports an onload attribute on an iframe element that is created through innerHTML or is statically already present in a document. W3 says nothing at all about an onload attribute for iframe or frame, only frameset: http://www.w3.org/TR/REC-html40/present/frames.html#h-16.5 |
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InFix acquired Wind River AS which acquired ICEStorm from norwegian icesoft.no . Uses Mozilla Rhino for javascript. |
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Opera. FYI, they call their engine "Presto" |
1.3.4