jquery - trying to set the data value of submit button -

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• append select option html5 data attribute using jquery 1 answer

i've been having problems trying set data value of elment. have following:

<textarea class='pairing-comment' ></textarea> <input data-comment="" data-global-id="187"        type="submit" id="pairing-comment-submit"> 

i'd update the data-comment value when user changes textarea (testing has shown reliable way done):

$('textarea.pairing-comment').on('keyup',function() {     var com = $(this).val();     console.log("here in pairing-comment " + com);  // works fine     $('#pairing-comment-submit').          data('comment', com);  // not writing data-comment elment }); 

what jquery syntax write want data-comment value?

thx

if want attribute data-comment updated, have use

$('#pairing-comment-submit').attr('data-comment', com); 

when use .data(), updates value internal data structure maintained jquery instead of changing attribute value

demo: fiddle