Javascript 如何按顺序执行3个异步函数?
代码如下:Javascript 如何按顺序执行3个异步函数?,javascript,Javascript,代码如下: adjust_geo = function(callback){Plasma.Hose('edge-to-sluice').Deposit({ "descrips": [ "sluice", "prot-spec v1.0", "request", "zoom" ], "ingests": { "lat":
adjust_geo = function(callback){Plasma.Hose('edge-to-sluice').Deposit({
"descrips": [
"sluice",
"prot-spec v1.0",
"request",
"zoom"
],
"ingests": {
"lat": stickie.latitude,
"lon": stickie.longitude,
"level": stickie.zoom_level
}
});
Plasma.Hose('edge-to-sluice').Deposit({
"descrips": [
"sluice",
"prot-spec v1.0",
"request",
"set-time"
],
"ingests": {
"time": stickie.start,
"rate": 2.0,
"pause": false
}
});
callback();
}
var remove_stickies = function(callback){
Plasma.Hose('edge-to-sluice').Deposit({ descrips: ['sluice', 'prot-spec v1.0', 'request', 'remove-all-fluoro'], ingests : {}
});
callback();
}
deposit_fluoros = function(){
console.log(stickie.fluoroscopes);
L = JSON.parse(stickie.fluoroscopes);
console.log(L);
for (var i = 1; i<L.length;i++){
console.log(L[i]);
Plasma.Hose('tcp://localhost/edge-to-sluice')
.Deposit({
"descrips": [
"sluice",
"prot-spec v1.0",
"request",
"new-fluoro-instance"],
"ingests":L[i]
});
};
}
}
adjust_geo(remove_stickies(deposit_fluoros()));
adjust_geo=函数(回调){Plasma.hope('edge-to-slucte')。存款({
“描述”:[
“水闸”,
“保护规范v1.0”,
“请求”,
“缩放”
],
“摄入”:{
“纬度”:粘性纬度,
“lon”:粘滞的经度,
“级别”:粘滞。缩放\u级别
}
});
等离子软管(“边缘到水闸”)。沉积物({
“描述”:[
“水闸”,
“保护规范v1.0”,
“请求”,
“设定时间”
],
“摄入”:{
“时间”:stickie.start,
“利率”:2.0,
“暂停”:错误
}
});
回调();
}
var remove_stickies=函数(回调){
Plasma.hope('edge-to-Sluck')。沉积物({描述:['Sluck','prot spec v1.0','request','remove all fluoro'],摄入:{}
});
回调();
}
存款=功能(){
控制台日志(胶粘荧光镜);
L=JSON.parse(stickie.fluoroscopes);
控制台日志(L);
对于(var i=1;i将最后一行更改为
adjust_geo(remove_stickies(deposit_fluoros));
按照您当前的操作方式,您正在传递deposit\u fluoros的结果,而不是传递对函数的引用。删除了所有其他对象,只是普通回调。放回您的对象,它就会工作。无论何时返回或调用回调,请确保将其作为函数返回
var adjust_geo = function (callback) {
callback();
console.log('adjust_geo');
}
// wrap the result of first call into a function and return it
var remove_stickies = function (callback) {
return function () {
callback()
console.log('remove_stickies');
};
}
var deposit_fluoros = function () {
console.log('deposit_fluoros')
};
adjust_geo(remove_stickies(deposit_fluoros));
输出:
"deposit_fluoros"
"remove_stickies"
"adjust_geo"
最后一行出现问题(您必须传递回调函数,而不是进行函数调用),并且您必须将回调传递到所有函数中,或者在传递回调时签入代码:
adjust_geo(
function(){
remove_stickies(
deposit_fluoros
)
});
这将调用调整\u geo,回调将调用移除\u胶粘物,回调将调用存款\u透视图
如果Plasma.hope(“…”).Deposit
看起来像Plasma.hope(“…”).Deposit(data,doneCallback)
您可以通过将下一个函数调用移动到doneCallback
中来更新代码以按顺序运行函数:
adjust_geo = function(callback) {
Plasma.Hose('edge-to-sluice').Deposit({
"descrips": [
"sluice",
"prot-spec v1.0",
"request",
"zoom"
],
"ingests": {
"lat": stickie.latitude,
"lon": stickie.longitude,
"level": stickie.zoom_level
}
},
function() {
Plasma.Hose('edge-to-sluice').Deposit({
"descrips": [
"sluice",
"prot-spec v1.0",
"request",
"set-time"
],
"ingests": {
"time": stickie.start,
"rate": 2.0,
"pause": false
}
}, callback)
}
);
}
var remove_stickies = function(callback) {
Plasma.Hose('edge-to-sluice').Deposit({
descrips: ['sluice', 'prot-spec v1.0', 'request', 'remove-all-fluoro'],
ingests: {}
}, callback);
}
deposit_fluoros = function() {
console.log(stickie.fluoroscopes);
L = JSON.parse(stickie.fluoroscopes);
console.log(L);
for (var i = 1; i < L.length; i++) {
console.log(L[i]);
Plasma.Hose('tcp://localhost/edge-to-sluice')
.Deposit({
"descrips": [
"sluice",
"prot-spec v1.0",
"request",
"new-fluoro-instance"
],
"ingests": L[i]
});
};
}
}
adjust_geo(
function() {
remove_stickies(
deposit_fluoros
)
});
adjust\u geo=函数(回调){
等离子软管(“边缘到水闸”)。沉积物({
“描述”:[
“水闸”,
“保护规范v1.0”,
“请求”,
“缩放”
],
“摄入”:{
“纬度”:粘性纬度,
“lon”:粘滞的经度,
“级别”:粘滞。缩放\u级别
}
},
函数(){
等离子软管(“边缘到水闸”)。沉积物({
“描述”:[
“水闸”,
“保护规范v1.0”,
“请求”,
“设定时间”
],
“摄入”:{
“时间”:stickie.start,
“利率”:2.0,
“暂停”:错误
}
},回调)
}
);
}
var remove_stickies=函数(回调){
等离子软管(“边缘到水闸”)。沉积物({
描述:[“水闸”、“保护规范v1.0”、“请求”、“移除所有荧光灯”],
摄取:{}
},回调);
}
存款=功能(){
控制台日志(胶粘荧光镜);
L=JSON.parse(stickie.fluoroscopes);
控制台日志(L);
对于(变量i=1;i
Promissions是一种方法。避免回调异步函数,这会很快让您感到困惑。在34上出现错误的原因是回调()在remove_stickies函数外部调用。所需的执行顺序是什么?adjust_geo
、remove_stickies
和deposit_fluoros
?@Igor它应该是adjust_geo,然后remove_stickies,然后deposit_fluoros@user3727514-那么VitaliyG的回答就是你的答案嗯,这不会给出任何未定义的错误但它似乎仍然按照移除粘滞物、放置透视图、调整地理位置的顺序进行。也许我应该改用promises?更新了我的答案-如果你在有console.log语句的地方添加代码,它就会按顺序进行。promises还依赖于幕后回调,因此它不是一对另一。也没有浏览器支持promi本机ses可靠这不会将回调传递到adjust\u geo
这对我来说很有意义,现在控制台正在以正确的顺序记录adjust\u geo、remove\u stickies、deposit\u fluoros。但是函数本身似乎仍然以错误的顺序执行。函数内部的回调是否可能是在主代码块(Plasma.Hose…)完成之前执行?实际上,这个问题中的所有函数都不是异步的。我猜Plasma.Hose(“…”).Deposit
是异步的,在这种情况下,您必须在这个函数中传递回调
。