js使用generator函数同步执行ajax任务

function request(url, callback) {

   fetch(url, {mode: 'cors' , credentials: 'include' , headers: new Headers({ 'X-Requested-With' : 'XMLHttpRequest' })})

   .then(response => response.text())

   .then(text => {

     console.log(url);

     console.log(text);

     callback(text);

   })

   . catch ((e) => console.log(e));

}

 

var iterator = null ;

function getData(src){

   request(src, function (response){

     iterator.next(JSON.parse(response));

   })

}

 

function getTpl(src){

   request(src, function (response){

     iterator.next(response);

   });

}

 

// 同步任务

function render(data, tpl){

   for ( var i in data) {

     tpl = tpl.replace( "${" +i+ "}" , data[i]);

   }

   return tpl;

}

 

// 主逻辑

var getArticles = function * (src){

   console.log( 'begin' )

   var data = yield getData(src)

   var tpl = yield getTpl(data.tpl)

   var res = render(data, tpl)

   console.log(res)

}

 

iterator = getArticles( 'data.json' )

// 开始执行

iterator.next()

// 异步任务模型