在处理 Moment JS 时遇到问题 (Angular)
Having trouble dealing with Moment JS (Angular)
我在使用 Moment JS 时遇到问题。基本上,我有一些广播电台的元数据,在我的 php 调用中,我进入 return 歌曲的 'duration',歌曲开始时的 'timestamp'。
我用Moment JS做了一些计算,得到歌曲结束的时间,然后我发现了不同。但是,不同之处在于 return 是一个负数,这会破坏应用程序。
如果有人能帮助我,那就太好了。
这是我的笑话http://plnkr.co/edit/joVLYdTKY5dZBOTNfTOI
服务
angular.module('starter', [])
.run(function(CurrentTrack){
CurrentTrack.refreshTrackData();
})
.controller('radioCtrl', function($scope,CurrentTrack) {
console.log(CurrentTrack);
$scope.CurrentTrack = CurrentTrack;
})
.service('CurrentTrack',function(radioData,$timeout){
var currentTrack = this;
this.setTrackData = function(trackData){
currentTrack.coverUrl = trackData.cover_url;
currentTrack.title = trackData.title;
currentTrack.artist = trackData.artist;
currentTrack.duration = moment.duration(parseInt(trackData.duration));
currentTrack.startedAt = moment.unix(trackData.timestamp);
currentTrack.finishesAt = moment(this.startedAt.add(this.duration));
currentTrack.updateIn = this.finishesAt.diff(moment());
currentTrack.refreshing = false;
return currentTrack.updateIn;
}
this.refreshTrackData = function(){
currentTrack.refreshing = true;
return radioData.refresh()
.then(currentTrack.setTrackData.bind(currentTrack))
.then(currentTrack.scheduleUpdate);
}
this.scheduleUpdate = function(ms){
console.log(ms)
$timeout(function(){
currentTrack.refreshTrackData()
},ms);
return;
}
})
工厂
.factory('radioData', function($http,$timeout) {
var retries = 0;
function parseResponse(response){
retries = 0;
if(!response.data.results){
console.log('no results')
return false;
}
console.log('refreshed...')
return response.data.results[0];
}
function makeRequest(){
console.log('refreshing...')
return $http.get('http://radio-sante-animale.fr/blah11.php? callback=jsonpCallback')
}
function retry(errResponse){
console.error('timed out');
//wait for a sec
retries++;
if(retries > 5){
throw new Error('timed out after 5 attempts!');
}
//oops
return $timeout(makeRequest,1000).then(null,retry);
}
var radioData = {
refresh: function() {
return makeRequest()
.then(null,retry)
.then(parseResponse)
.catch(function(err){
console.log(err);
});
}
};
return radioData;
});
来自http://momentjs.com/docs/#/displaying/difference/
If the moment is earlier than the moment you are passing to
moment.fn.diff, the return value will be negative.
您需要反转 diff 中的日期。
编辑:像这样 -
currentTrack.updateIn = moment().diff(this.finishesAt);
首先我改变了:
currentTrack.finishesAt = moment(this.startedAt.add(this.duration));
至:
currentTrack.finishesAt = moment(currentTrack.startedAt).add(currentTrack.duration);
在原始代码中,您正在改变 startedAt
时间然后进行克隆。我还将所有 this
更改为 currentTrack
以使其更加一致。
问题
当服务器保持的时间和客户端保持的时间不同时,错误就会出现(不是因为你有任何颠倒)。
基本上,服务器会向您发送 trackData.timestamp
,您可以将其解析并转换为片刻以用作您的 startedAt
时间。然后将 trackData.duration
更改为 moment.duration
并将其添加到 startedAt
时间以获得 finishesAt
时间。
如果客户端保持的时间比服务器时间早运行,则计算出的finishesAt
时间将早于歌曲实际结束的时间。一个夸张的例子使这一点更清楚。
var app = angular.module('app', []);
app.controller('myController', function($scope, $timeout, $interval, Server) {
function updateTime() {
$scope.serverTime = moment().subtract(1,'s');
$scope.clientTime = moment();
}
function refreshInfo() {
Server.getSongInfo().then(parseInfo).then(scheduleRefresh);
};
function parseInfo(trackData) {
$scope.songInfo = trackData;
var startedAt = trackData.timestamp;
$scope.finishesAt = moment(startedAt).add(trackData.duration, 'ms');
$scope.updateIn = $scope.finishesAt.diff(moment());
return $scope.updateIn;
}
function scheduleRefresh(updateIn) {
if (updateIn < 0) {
$scope.bugged = true;
} else {
$scope.bugged = false;
}
$timeout(refreshInfo, updateIn);
}
$scope.songInfo = "loading";
updateTime();
refreshInfo();
$interval(updateTime, 1000);
});
app.service('Server', function($timeout, $interval) {
var song = {
duration: 5000
};
this.getSongInfo = function() {
return $timeout(function() { return this.trackData });
};
function nextSong() {
this.trackData = {
duration: song.duration,
timestamp: moment().subtract(1,'s')
};
}
nextSong();
$interval(nextSong, song.duration);
});
.container {
display: flex;
flex-flow: row wrap;
}
.row {
display: flex;
flex-direction: row;
flex-flow: space-around;
width: 100%;
}
.col {
margin: auto;
text-align: center;
}
.red {
background-color: red;
}
<head>
<script data-require="angular.js@1.4.0-beta.3" data-semver="1.4.0-beta.3" src="https://code.angularjs.org/1.4.0-beta.3/angular.js"></script>
<script data-require="moment.js@2.8.3" data-semver="2.8.3" src="//cdnjs.cloudflare.com/ajax/libs/moment.js/2.8.3/moment.min.js"></script>
</head>
<div ng-app='app' ng-controller='myController'>
<div class="container">
<div class='row'>
<div class='col' ng-class='{red:bugged}'>
<h3>Song Info</h3>
<div>{{ songInfo }}</div>
</div>
</div>
<div class="row">
<div class='col'>
<h3>Server</h3>
<div>{{ serverTime.format("hh:mm:ss") }}</div>
</div>
<div class='col'>
<h3>Finishes At</h3>
<div>{{ finishesAt.format("hh:mm:ss") }}</div>
</div>
<div class='col'>
<h3>Update In</h3>
<div>{{ updateIn }}</div>
</div>
<div class='col'>
<h3>Client</h3>
<div>{{ clientTime.format("hh:mm:ss") }}</div>
</div>
</div>
</div>
</div>
Whenever the song info div is red, the client is in the loop where it is requesting new track info and parsing out a finish time that is earlier than the current moment, which immediately makes it request new track info.
angular.module('starter', [])
.run(function(CurrentTrack) {
CurrentTrack.refreshTrackData();
})
.controller('radioCtrl', function($scope, CurrentTrack) {
$scope.CurrentTrack = CurrentTrack;
})
.service('CurrentTrack', function(radioData, $timeout) {
var currentTrack = this;
this.setTrackData = function(trackData) {
currentTrack.coverUrl = trackData.cover_url;
currentTrack.title = trackData.title;
currentTrack.artist = trackData.artist;
currentTrack.duration = moment.duration(parseInt(trackData.duration));
currentTrack.startedAt = moment.unix(trackData.timestamp);
currentTrack.finishesAt = moment(currentTrack.startedAt).add(currentTrack.duration);
currentTrack.updateIn = currentTrack.finishesAt.diff(moment())
console.log(currentTrack, trackData);
currentTrack.refreshing = false;
return currentTrack.updateIn;
}
this.refreshTrackData = function() {
currentTrack.refreshing = true;
return radioData.refresh()
.then(currentTrack.setTrackData)
.then(currentTrack.scheduleUpdate);
}
this.scheduleUpdate = function(ms) {
console.log("update in " + ms)
$timeout(function() {
currentTrack.refreshTrackData()
}, ms);
return;
}
})
.factory('radioData', function($http, $timeout) {
var retries = 0;
function parseResponse(response) {
retries = 0;
if (!response.data.results) {
console.log('no results')
return false;
}
console.log('response parsed.')
return response.data.results[0];
}
function makeRequest() {
console.log('making request.')
return $http.get('http://radio-sante-animale.fr/blah11.php?callback=jsonpCallback')
}
function retry(errResponse) {
console.error('timed out');
//wait for a sec
retries++;
if (retries > 5) {
throw new Error('timed out after 5 attempts!');
}
//oops
return $timeout(makeRequest, 1000).then(parseResponse, retry);
}
var radioData = {
refresh: function() {
return makeRequest()
.then(parseResponse, retry)
.catch(function(err) {
console.log(err);
});
}
};
return radioData;
});
<!DOCTYPE html>
<html ng-app="starter">
<head>
<script data-require="angular.js@1.4.0-beta.3" data-semver="1.4.0-beta.3" src="https://code.angularjs.org/1.4.0-beta.3/angular.js"></script>
<script data-require="moment.js@2.8.3" data-semver="2.8.3" src="//cdnjs.cloudflare.com/ajax/libs/moment.js/2.8.3/moment.min.js"></script>
</head>
<body ng-controller="radioCtrl">
<h3>Current Music Information</h3>
<p ng-show="CurrentTrack.refreshing">refreshing...</p>
<img style="width:300px;height:300px;" src="{{CurrentTrack.coverUrl}}" alt="">
<p>
Title : {{ CurrentTrack.title }}
<br />Artist : {{ CurrentTrack.artist }}
<br />The song started at {{ CurrentTrack.startedAt }}
<br />Duration of the song {{ CurrentTrack.duration.asSeconds() }} seconds
<br />Finishes At {{ CurrentTrack.finishesAt }}
<br />Update In {{ CurrentTrack.updateIn }}
<br />
</body>
</html>
实际上我不确定解决此问题的最佳方法,但希望有人有更好的答案。
一个 hack 解决方案是为 finishesAt
添加更多时间(一些可接受的错误量)以留出一点回旋余地。
currentTrack.finishesAt = moment(currentTrack.startedAt).add(currentTrack.duration).add(1, 's');
在我这边,它通过在你的 $timeout 方法
中添加 Math.abs 来工作
this.scheduleUpdate = function(ms) {
console.log( 'update in :' + ms)
$timeout(function() {
currentTrack.refreshTrackData()
}, Math.abs(ms));
return;
}
我在使用 Moment JS 时遇到问题。基本上,我有一些广播电台的元数据,在我的 php 调用中,我进入 return 歌曲的 'duration',歌曲开始时的 'timestamp'。
我用Moment JS做了一些计算,得到歌曲结束的时间,然后我发现了不同。但是,不同之处在于 return 是一个负数,这会破坏应用程序。
如果有人能帮助我,那就太好了。
这是我的笑话http://plnkr.co/edit/joVLYdTKY5dZBOTNfTOI
服务
angular.module('starter', [])
.run(function(CurrentTrack){
CurrentTrack.refreshTrackData();
})
.controller('radioCtrl', function($scope,CurrentTrack) {
console.log(CurrentTrack);
$scope.CurrentTrack = CurrentTrack;
})
.service('CurrentTrack',function(radioData,$timeout){
var currentTrack = this;
this.setTrackData = function(trackData){
currentTrack.coverUrl = trackData.cover_url;
currentTrack.title = trackData.title;
currentTrack.artist = trackData.artist;
currentTrack.duration = moment.duration(parseInt(trackData.duration));
currentTrack.startedAt = moment.unix(trackData.timestamp);
currentTrack.finishesAt = moment(this.startedAt.add(this.duration));
currentTrack.updateIn = this.finishesAt.diff(moment());
currentTrack.refreshing = false;
return currentTrack.updateIn;
}
this.refreshTrackData = function(){
currentTrack.refreshing = true;
return radioData.refresh()
.then(currentTrack.setTrackData.bind(currentTrack))
.then(currentTrack.scheduleUpdate);
}
this.scheduleUpdate = function(ms){
console.log(ms)
$timeout(function(){
currentTrack.refreshTrackData()
},ms);
return;
}
})
工厂
.factory('radioData', function($http,$timeout) {
var retries = 0;
function parseResponse(response){
retries = 0;
if(!response.data.results){
console.log('no results')
return false;
}
console.log('refreshed...')
return response.data.results[0];
}
function makeRequest(){
console.log('refreshing...')
return $http.get('http://radio-sante-animale.fr/blah11.php? callback=jsonpCallback')
}
function retry(errResponse){
console.error('timed out');
//wait for a sec
retries++;
if(retries > 5){
throw new Error('timed out after 5 attempts!');
}
//oops
return $timeout(makeRequest,1000).then(null,retry);
}
var radioData = {
refresh: function() {
return makeRequest()
.then(null,retry)
.then(parseResponse)
.catch(function(err){
console.log(err);
});
}
};
return radioData;
});
来自http://momentjs.com/docs/#/displaying/difference/
If the moment is earlier than the moment you are passing to moment.fn.diff, the return value will be negative.
您需要反转 diff 中的日期。
编辑:像这样 -
currentTrack.updateIn = moment().diff(this.finishesAt);
首先我改变了:
currentTrack.finishesAt = moment(this.startedAt.add(this.duration));
至:
currentTrack.finishesAt = moment(currentTrack.startedAt).add(currentTrack.duration);
在原始代码中,您正在改变 startedAt
时间然后进行克隆。我还将所有 this
更改为 currentTrack
以使其更加一致。
问题
当服务器保持的时间和客户端保持的时间不同时,错误就会出现(不是因为你有任何颠倒)。
基本上,服务器会向您发送 trackData.timestamp
,您可以将其解析并转换为片刻以用作您的 startedAt
时间。然后将 trackData.duration
更改为 moment.duration
并将其添加到 startedAt
时间以获得 finishesAt
时间。
如果客户端保持的时间比服务器时间早运行,则计算出的finishesAt
时间将早于歌曲实际结束的时间。一个夸张的例子使这一点更清楚。
var app = angular.module('app', []);
app.controller('myController', function($scope, $timeout, $interval, Server) {
function updateTime() {
$scope.serverTime = moment().subtract(1,'s');
$scope.clientTime = moment();
}
function refreshInfo() {
Server.getSongInfo().then(parseInfo).then(scheduleRefresh);
};
function parseInfo(trackData) {
$scope.songInfo = trackData;
var startedAt = trackData.timestamp;
$scope.finishesAt = moment(startedAt).add(trackData.duration, 'ms');
$scope.updateIn = $scope.finishesAt.diff(moment());
return $scope.updateIn;
}
function scheduleRefresh(updateIn) {
if (updateIn < 0) {
$scope.bugged = true;
} else {
$scope.bugged = false;
}
$timeout(refreshInfo, updateIn);
}
$scope.songInfo = "loading";
updateTime();
refreshInfo();
$interval(updateTime, 1000);
});
app.service('Server', function($timeout, $interval) {
var song = {
duration: 5000
};
this.getSongInfo = function() {
return $timeout(function() { return this.trackData });
};
function nextSong() {
this.trackData = {
duration: song.duration,
timestamp: moment().subtract(1,'s')
};
}
nextSong();
$interval(nextSong, song.duration);
});
.container {
display: flex;
flex-flow: row wrap;
}
.row {
display: flex;
flex-direction: row;
flex-flow: space-around;
width: 100%;
}
.col {
margin: auto;
text-align: center;
}
.red {
background-color: red;
}
<head>
<script data-require="angular.js@1.4.0-beta.3" data-semver="1.4.0-beta.3" src="https://code.angularjs.org/1.4.0-beta.3/angular.js"></script>
<script data-require="moment.js@2.8.3" data-semver="2.8.3" src="//cdnjs.cloudflare.com/ajax/libs/moment.js/2.8.3/moment.min.js"></script>
</head>
<div ng-app='app' ng-controller='myController'>
<div class="container">
<div class='row'>
<div class='col' ng-class='{red:bugged}'>
<h3>Song Info</h3>
<div>{{ songInfo }}</div>
</div>
</div>
<div class="row">
<div class='col'>
<h3>Server</h3>
<div>{{ serverTime.format("hh:mm:ss") }}</div>
</div>
<div class='col'>
<h3>Finishes At</h3>
<div>{{ finishesAt.format("hh:mm:ss") }}</div>
</div>
<div class='col'>
<h3>Update In</h3>
<div>{{ updateIn }}</div>
</div>
<div class='col'>
<h3>Client</h3>
<div>{{ clientTime.format("hh:mm:ss") }}</div>
</div>
</div>
</div>
</div>
Whenever the song info div is red, the client is in the loop where it is requesting new track info and parsing out a finish time that is earlier than the current moment, which immediately makes it request new track info.
angular.module('starter', [])
.run(function(CurrentTrack) {
CurrentTrack.refreshTrackData();
})
.controller('radioCtrl', function($scope, CurrentTrack) {
$scope.CurrentTrack = CurrentTrack;
})
.service('CurrentTrack', function(radioData, $timeout) {
var currentTrack = this;
this.setTrackData = function(trackData) {
currentTrack.coverUrl = trackData.cover_url;
currentTrack.title = trackData.title;
currentTrack.artist = trackData.artist;
currentTrack.duration = moment.duration(parseInt(trackData.duration));
currentTrack.startedAt = moment.unix(trackData.timestamp);
currentTrack.finishesAt = moment(currentTrack.startedAt).add(currentTrack.duration);
currentTrack.updateIn = currentTrack.finishesAt.diff(moment())
console.log(currentTrack, trackData);
currentTrack.refreshing = false;
return currentTrack.updateIn;
}
this.refreshTrackData = function() {
currentTrack.refreshing = true;
return radioData.refresh()
.then(currentTrack.setTrackData)
.then(currentTrack.scheduleUpdate);
}
this.scheduleUpdate = function(ms) {
console.log("update in " + ms)
$timeout(function() {
currentTrack.refreshTrackData()
}, ms);
return;
}
})
.factory('radioData', function($http, $timeout) {
var retries = 0;
function parseResponse(response) {
retries = 0;
if (!response.data.results) {
console.log('no results')
return false;
}
console.log('response parsed.')
return response.data.results[0];
}
function makeRequest() {
console.log('making request.')
return $http.get('http://radio-sante-animale.fr/blah11.php?callback=jsonpCallback')
}
function retry(errResponse) {
console.error('timed out');
//wait for a sec
retries++;
if (retries > 5) {
throw new Error('timed out after 5 attempts!');
}
//oops
return $timeout(makeRequest, 1000).then(parseResponse, retry);
}
var radioData = {
refresh: function() {
return makeRequest()
.then(parseResponse, retry)
.catch(function(err) {
console.log(err);
});
}
};
return radioData;
});
<!DOCTYPE html>
<html ng-app="starter">
<head>
<script data-require="angular.js@1.4.0-beta.3" data-semver="1.4.0-beta.3" src="https://code.angularjs.org/1.4.0-beta.3/angular.js"></script>
<script data-require="moment.js@2.8.3" data-semver="2.8.3" src="//cdnjs.cloudflare.com/ajax/libs/moment.js/2.8.3/moment.min.js"></script>
</head>
<body ng-controller="radioCtrl">
<h3>Current Music Information</h3>
<p ng-show="CurrentTrack.refreshing">refreshing...</p>
<img style="width:300px;height:300px;" src="{{CurrentTrack.coverUrl}}" alt="">
<p>
Title : {{ CurrentTrack.title }}
<br />Artist : {{ CurrentTrack.artist }}
<br />The song started at {{ CurrentTrack.startedAt }}
<br />Duration of the song {{ CurrentTrack.duration.asSeconds() }} seconds
<br />Finishes At {{ CurrentTrack.finishesAt }}
<br />Update In {{ CurrentTrack.updateIn }}
<br />
</body>
</html>
实际上我不确定解决此问题的最佳方法,但希望有人有更好的答案。
一个 hack 解决方案是为 finishesAt
添加更多时间(一些可接受的错误量)以留出一点回旋余地。
currentTrack.finishesAt = moment(currentTrack.startedAt).add(currentTrack.duration).add(1, 's');
在我这边,它通过在你的 $timeout 方法
中添加 Math.abs 来工作this.scheduleUpdate = function(ms) {
console.log( 'update in :' + ms)
$timeout(function() {
currentTrack.refreshTrackData()
}, Math.abs(ms));
return;
}