chrome扩展开发其他地方调用sendmessage里的response

Question

var sysconfig={};

 chrome.runtime.sendMessage({type : 'getload'}, function(response){
            sysconfig=response.configs;
            console.log(sysconfig);//可以打印出来
    });

console.log(system);///打印为空对象

background.js里是

 case 'getload':
            sendResponse({configs:main.config});
            break;

为什么在sendMessage外获取不到数据啊