jquery 自定义input输入监听事件

网上一段JS，考来的，自定义监听：

    $.event.special.valuechange = {      teardown: function (namespaces) {        $(this).unbind('.valuechange');      },      handler: function (e) {        $.event.special.valuechange.triggerChanged($(this));      },      add: function (obj) {        $(this).on('keyup.valuechange cut.valuechange paste.valuechange input.valuechange',         obj.selector, $.event.special.valuechange.handler)      },      triggerChanged: function (element) {        var current = element[0].contentEditable === 'true' ? element.html() : element.val()          , previous = typeof element.data('previous') === 'undefined' ? element[0].defaultValue : element.data('previous')        if (current !== previous) {          element.trigger('valuechange', [element.data('previous')])          element.data('previous', current)        }      }    }

使用时：

$(".class").on("valuechange",function(){        your function        });