javascript - 在我的例子中如何仅发送一次 AJAX 调用

Question

我对如何编写这个逻辑感到困惑。我要寻找的是视频何时播放，并且如果视频观看百分比超过 2%，我想发送一次 AJAX 请求。但实际发生的情况是它会持续从2% 到 100%

触发

如果我写=(等于)而不是>(大于)，它不会触发，因为我没有对数字进行四舍五入，所以由于小数，它不会触发。那么在这种情况下我该如何编写这个逻辑呢？AJAX 请求只能发送一次。

var j = 0;
$("#video").bind("timeupdate", function() {
  var currentTime = this.currentTime;
  var totalPlayed = 0;
  var played = video.played;
  for (var i = 0; i < played.length; i++) {
    totalPlayed += played.end(i) - played.start(i);
    var  playedInPercentage = (totalPlayed/totalTime)*100;
  }
/*here i want to write a logic to send this lowered only once.*/
  if (totalPlayed > 0.02*(totalTime)) { //watched 2% and above then this will excute 0.02(2%)
    alert("asdsad");
    if(j < 1) {
        /* Ajax call  video watched starts here it should trigger only once*/
        $.ajax({
            url: "student_learning_controller.php",
            method: "POST",
            data: {'action': 'videoWatched', 'course_id': course_id,'videoId' : videoId,'totalVideoTime':totalTime,'totalPlayedTime':totalPlayed,'percentagePlayed':playedInPercentage },
            dataType: "json",

            success: function (response) {
                if (response["success"] == true) {
                    $("#success_message").html(response["message"]);    

                }
            },
            error: function (request, status, error) {
                $("#warning_message").show();
                $("#warning_message").html("OOPS! Something Went Wrong Please Try After Sometime!");
            }
        });
        /* Ajax call  video watched ends here */
    }
    j += 1; //Reset for duplicates (repeated playback)
}
});     

Answer 1

您可以在“if”之前使用var returned = 0;。

然后“if”变为: if(totalPlayed > 0.02*(totalTime) && !triggered ){triggered = 1;

这只会执行一次，因为当您输入“if”时，您将更新“triggered”变量，并且不会再次输入“if”。