如果jQuery.ajax等待响应时间足够长，则运行函数

像这样：

var cancelMe = setTimeout(function() {   $('#loading').show(); // assuming your loading element has the id "loading"}, 2000); // show loading element in 2 secondsjQuery.ajax({    url: "loadData.php",    dataType: 'json',    type: 'GET',    success: function(result){        showResultsToUser(result);        clearTimeout(cancelMe); // don't run if it hasn't run yet        $('#loading').hide(); // hide the loading element if it's shown    }});