jquery判断对象是否为空并遍历对象的简单实例

if(document.getElementById("target_obj_id")){} else {}

1. var target_obj = jQuery('#target_obj_id');  if (target_obj.length > 0) { //如果大于0 标识 id 为target_obj_id的对象存在，否则不存在  } else {  }2、 if (target_obj[0]) {  } else { }3. $.isEmptyObject({}) // true  $.isEmptyObject({ foo: "bar" }) // false//判断并遍历每个对象if($("#t_specialsearch select").length <= 0){          alert("对象为空");}else{    //console.log($("#t_specialsearch select")[0]);    $("#t_specialsearch select").each(function(){      //alert($(this));      console.log($(this));    });    for(var i in $("#t_specialsearch select")){      console.log($("#t_specialsearch select")[i]);    }}