javascript性能优化之分时函数的介绍

function timeChunk( arr, fn, count){//arr 数组 fn操作函数 count每次操作数量
  var obj,
    t;
  var start = function(){
    var len = Math.min(count||1,arr.length);
    for(var i=0; i < len; i++){
      obj = arr.shift();
      fn(obj)
    }
  };
  return function(interval){
    t = setInterval(function(){
      if(arr.length==0){
        return clearInterval(t)
      };
      start();
    },interval||200)
  }
}

var arr = [];
for(var i = 1; i <= 1000; i++){
  arr.push(i)
}
var renderLists = timeChunk(arr,function(i){
  var div = document.createElement('div');
  div.innerHTML = i;
  document.body.appendChild(div);
},20);
renderLists(200);