jquery - Explain what is happening in this code -


really stuck trying figure out happening in code below... 

function updatecolourdropdown(url) {     $("#selectlist").unbind();     $.post(setuniqueparam(url), $("#fruitform").serialize(),             function(data) {                 if (checkexception(data)) {                     $("#fruitdiv").children().each(function() {                         removeelem(this);                     }).end().html(data);                     $("#selectlist").change(function() {                         updatecolourdropdown($("#fruitcolourview").val());                     });                     organiseallocateteams();                 }                 data = null;             }     );     return false; }

basically there form containing 2 dropdown lists, fruit , colour. if user changes fruit in first select list, call server made find out available colours populate second select list.

my html output using jsp..

selectlist = id of select list containing list of fruits,

fruitform = id of form containing select lists

fruitdiv = id of div wraps around 2 select lists

fruitcolourview = id of hidden input field used link struts action (xml)

this working code. trying replicate code on page, i'm finding bit tricky not sure doing, , why... can tell 'data' variable contains entire code page..

i have looked .children .each .end etc etc on jquery website cannot logically put together...

thanks heaps, hope have been clear enough.

function updatecolourdropdown(url) {     // remove handlers on #selectlist     $("#selectlist").unbind();      // post url specified in parameter, serializing #fruitform     $.post(setuniqueparam(url), $("#fruitform").serialize(),              // run on success             function(data) {                  // assuming `checkexception` looks in returned                 // data see if went wrong.                 if (checkexception(data)) {                      // went wrong; each of #fruitdiv's children                      // run function removes child element,                     // @ end, put data, appears html,                     // #fruitdiv                     $("#fruitdiv").children().each(function() {                         removeelem(this);                     }).end().html(data);                      // set new `change` event handler on #selectlist                     // runs `updatecolourdropdown, given value of                     // #fruitcolourview. see note 1.                     $("#selectlist").change(function() {                         updatecolourdropdown($("#fruitcolourview").val());                     });                      // call this.                     organiseallocateteams();                 }                  // useless.                 data = null;             }     );       return false; }

note 1: in reasonably current versions of jquery i'd handle handler uses event delegation avoid having unbind/rebind repeatedly.

the question has nothing struts, , there's not going on that's particularly difficult reason about.


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