javascript - 将 setTimeout 与 jQuery 一起使用

Question

我想在第一个 $.each 的每次迭代之间添加 500 毫秒的暂停

我不确定如何应用此解决方案: How to add pause between each iteration of jQuery .each()?

对于我的具体情况:

function iterateAddresses () {

  var time = 500;

  $.each( addresses_google, function( index, value ) {
    var service = new google.maps.DistanceMatrixService();

    service.getDistanceMatrix(
      {
        origins: [origin],
        destinations: value,
        travelMode: 'DRIVING'
      },
      callback
    );

    function callback(response, status) {
      var origins = response.originAddresses;
      var destinations = response.destinationAddresses;
      for (var i = 0; i < origins.length; i++) {
        var results = response.rows[i].elements;
        for (var j = 0; j < results.length; j++) {
          var element = results[j];
          if(element.status == "NOT_FOUND"){
            var distance = 0;
          } else {
            var distance = element.distance.value;
          }
          if(distance > radius){
            // Store postids in array
            postids_to_hide.push(
              addresses_postids[index][j]
            );
            // Hide elements where postid is in the postids_to_hide arrays
            $.each( postids_to_hide, function( index, value ) {
              $(".main_short_post_div").filter(function(){
                return $(this).attr('data-post-id') === value;
              }).hide();
            });
          } // end if d < r
        } // end for j
      } // end for i
    } // end callback function
  }); // end each addresses_google

}; // end iterateAddresses

iterateAddresses();

Answer 1

function asyncForEach(arr, cb) {
    return arr.reduce((p,c)=>{
        return p.then(()=>cb(c));
    }, Promise.resolve());
}
function wait(ms) {
    return ()=>new Promise(resolve=>setTimeout(resolve, ms));
}

const DELAY = 500; //ms
function iterateAddresses() {
    return asyncForEach(addresses_google, address => 
      getDistanceMatrix(address)
        .then(processResult)
        .then(wait(DELAY)));
}

iterateAddresses();

getDistanceMatrix 是您提供给 $.each 的函数的 promise 版本。

processResult 是 callback 的 promise 版本。