jQuery attr与prop的区别_ATHER Shu(A.S)的Blog

Properties generally affect the dynamic state of a DOM element without changing the serialized HTML attribute. 
Examples include the value property of input elements, the disabled property of inputs and buttons, or the checked property of a checkbox. 
The .prop() method should be used to set disabled and checked instead of the .attr() method. 
The .val() method should be used for getting and setting value.

$('input[name="reports_mode"]').prop('testProp', 'prop');
$('input[name="reports_mode"]').attr('testAttr', 'attr');            alert($('input[name="reports_mode"]').prop('testProp') + $('input[name="reports_mode"]').attr('testAttr'));

Nevertheless, the most important concept to remember about the checked attribute is that it does not correspond to the checked property. 
The attribute actually corresponds to the defaultChecked property and should be used only to set the initial value of the checkbox. 
The checked attribute value does not change with the state of the checkbox, while the checked property does. 
Therefore, the cross-browser-compatible way to determine if a checkbox is checked is to use the property:
if ( elem.checked )
if ( $( elem ).prop( "checked" ) )
if ( $( elem ).is( ":checked" ) )
The same is true for other dynamic attributes, such as selected and value.