欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  web前端

分享一篇改写成传统的回调函数实例教程

程序员文章站 2022-04-26 16:40:25
...
改写前:

百度地图中坐标转换的JavaScript API示例官方示例如下:

var points = [new BMap.Point(116.3786889372559,39.90762965106183),              new BMap.Point(116.38632786853032,39.90795884517671),              new BMap.Point(116.39534009082035,39.907432133833574),              new BMap.Point(116.40624058825688,39.90789300648029),              new BMap.Point(116.41413701159672,39.90795884517671)
];//地图初始化var bm = new BMap.Map("allmap");
bm.centerAndZoom(new BMap.Point(116.378688937,39.9076296510), 15);//坐标转换完之后的回调函数translateCallback = function (data){  if(data.status === 0) {for (var i = 0; i < data.points.length; i++) {
        bm.addOverlay(new BMap.Marker(data.points[i]));
        bm.setCenter(data.points[i]);
    }
  }
}
setTimeout(function(){var convertor = new BMap.Convertor();
    convertor.translate(points, 1, 5, translateCallback)
}, 1000);

改写后:

将上述代码改写为传统的JavaScript回调函数形式:

function translate(points,callback){  var convertor=new BMap.Convertor();
  convertor.translate(points, 1, 5, callback)
  translateCallback = function (data){if(data.status === 0) {      var res=[]; //res用来存放转换后的points数组  for (var i = 0; i < data.points.length; i++) {
          bm.addOverlay(new BMap.Marker(data.points[i]));
          res.push(data.points[i]);
      }
      callback(res)
    }
  }
}//再调用translate函数,translate(points,function(data){
    console.log(data); //data为转换后的points数组})

改写后translate函数接受两个参数,第一个参数为原始的百度points数组,第二个参数传入一个回调函数。

以上就是分享一篇改写成传统的回调函数实例教程的详细内容,更多请关注其它相关文章!