外部获取异步方法中的数据两种方式callback&Promise

callback

function getData(callback){
	setTimeout(function(){
		var name = 'smileyqp';
		callback(name);
	},1000);
}
getData(function(data){
	console.log(data);			//smileyqp
})

Promise

//写法一
var p= new Promise(function(resolve,reject){
	setTimeout(function(){
		var name = 'smileyqp';
		resolve(name);
	},1000);
});
p.then((data)=>{
	console.log(data);	//smileyqp
})

//写法二：
function getData(resolve,reject){
	setTimeout(function(){
		var name = 'smileyqp';
		resolve(name);
	},1000);
}
var p= new Promise(getDate);
p.then((data)=>{
	console.log(data);		//smileyqp
})