javascript - jQuery write value into the input field's "value" attribute -

i have input field, input type text:

<input type="text" id="show-val" value=""> <button id="get-val">val</button> 

on button click it's taking url somewhere else, need place value text field's value attribute.

what is:

$('#get-val').on('click', function(){     var url = 'http://example.com/'; //suppose our grabbed url     $('#show-val').val( url ); }); 

but if inspect input text can see it's not writing url value attribute, it's pasting value text field.

what tried:

$('#get-val').on('click', function(){     var url = 'http://example.com/'; //suppose our grabbed url     $('#show-val').prop( 'value', url ); //failed     $('#show-val').prop( 'placeholder', url ); //passed }); 

output is:

<input type="text" id="show-val" value placeholder="http://example.com/"> 

why failing writing text field's value attribute? how can write actually?

value property $('#show-val').val(url); correct.

however if want modify value attribute use $.fn.attr( attributename, value)

set 1 or more attributes set of matched elements.

code

$('#show-val').attr('value', url);