javascript - 你会如何在定时器上做一个 for 循环？

Question

做这样的事情最好的方法是什么？

for a in b
   #do this thing
   #wait a second, then continue the loop

在 js 中

var a, _i, _len;

for (_i = 0, _len = b.length; _i < _len; _i++) {
  a = b[_i];
  //do this thing
  //wait a second, then continue the loop
}

谢谢!

Answer 1

要每秒处理 for (i in b) 循环中的一个项目，直到您完成这些项目，您可以这样做:

var list = [];
// accumulate list of items to operate on into an array
// that can be incremented through
for (var i in b) {
    list.push(i);
}

function next() {
    if (list.length > 0) {
        var item = list.shift();
        // do something with the next item here

        // do the next iteration one second later
        setTimeout(next, 1000);
    }
}
// start it
next();