获取json数据中所有key集合

/**
 * 获取json数据中所有key
 */
function fetchResponseInfo(responseInfo){
    
    //判断是否为空
    if((!responseInfo || responseInfo.length <= 0))    {
           return;
    }

    //获取model
    var jsonCon = jQuery.parseJSON(responseInfo).model;
    if(!jsonCon){
        return;
    }
    
    //获取所有key
    var keyArr;
    if(jsonCon instanceof Array){
       //1-JSONArray
       if(jsonCon.length <= 0){
           return;
       }
       var arrOb = jsonCon[0];
       keyArr = Object.keys(arrOb);
    }else if(jsonCon instanceof Object){
       //2-JSONObject
       keyArr = Object.keys(jsonCon);
    }else{
       //3-Other
       return;
    }
    if(!keyArr || keyArr.length <= 0){
       return;
    }
    
    //组装数组
    var temOb;
    var lang = "java.lang.String";
    var description = "";
    var resArr = new Array();
    for(i = 0; i < keyArr.length; i ++){
       temOb = new Object();
       temOb.param = keyArr[i];
       temOb.lang = lang;
       temOb.description = description;
       resArr[i] = temOb;
    }
    return resArr;
    
}