当我将现有代码包装到Deferred中时，whenAllDone Promise/deferred javascript helper中的参数不起作用 [英] Arguments in whenAllDone promise/deferred javascript helper not working when I wrap existing code into a Deferred

问题描述

我正在尝试在TypeScript中实现以下内容:

但是，我的是以 [true | false，currentDeferredArguments] 形式的 flattened 数组.因此，当我循环遍历 $.each(arguments，function(i，args){)中的参数时，我的args从来都不是数组".第一个 args 只是一个来自 currentDeferred.resolve 调用的 boolean ，然后显然会破坏该循环中的逻辑.

如果我更改代码以仅按他的方式测试代码(如下所示)，则代码将按预期工作.

  var dfd1 = $ .Deferred();var dfd2 = $ .Deferred();setTimeout(function(){console.log('Resolve dfd2');dfd2.reject({"Options":currentOptions，"ErrorMessage":"Test 2"})；}，200)；setTimeout(function(){console.log('works dfd1');dfd1.reject({"Options":currentOptions，"ErrorMessage":"Test 1"})；}，100);$ .whenAllDone(dfd1，dfd2).then( 

那么如何正确包装对 submitCalculation 的原始调用以正确返回延迟的对象，从而使 whenAllDone 起作用?

解决方案

问题出在jquery的 when 方法中.

jquery.when:function(下级/*，...，subordinateN */){...

它的行像:

 //如果resolveValues仅包含一个Deferred，请使用它.延期=剩余=== 1?下属:jQuery.Deferred()， 

这会改变参数的形状，因此我不得不将其恢复为我的代码期望的通用形状(即，当多个deferreds传递给 whenAllDone 时，形状相同)

  const deferredArgs = jqueryWhenUsesSubordinate?[[arguments [0]，arguments [1]]]:参数$ .each(deferredArgs，function(i，resolveArgs){var target =！resolvedArgs [0]?失败:成功；var data = resolveArgs [1];target.push(data.length === 1?data [0]:data);}); 

I'm trying to implement the following in TypeScript: https://stackoverflow.com/a/15094263/166231

UPDATE 2 - The problem with original answer is that it doesn't support a single deferred. I modified his fiddle to reproduce the error. http://jsfiddle.net/3h6gwe1x/

UPDATE 1 - Issue is in my usage, so modifying question to indicate that more clearly.

Originally, I had a submitCalculation method that called .ajax, so I passed a callback handler in to be called when it was done. This all worked, but I have to prepare for having to run 1..N submitCalculation calls and wait until all were done. So this was my attempt to simply wrap the original call inside a Deferred.

const p = function() {
    const d = $.Deferred();

    try {
        that.rble.submitCalculation( 
            currentOptions,
            ( errorMessage, result ) => { 
                if ( errorMessage != undefined ) {
                    d.reject( { "Options": currentOptions, "ErrorMessage": errorMessage } );
                }
                else {
                    d.resolve( { "Options": currentOptions, "Result": result } );
                }
            } 
        );
    } catch (error) {
        d.reject( { "Options": currentOptions, "ErrorMessage": "ReSubmit.Pipeline exception: " + error } );
    }

    return d;
}

$.whenAllDone( p() ).then( 
   function( ... successes: { Options: KatAppOptions, Result: RBLResult }[] ) { ... },
   function( ... failures: { Options: KatAppOptions, ErrorMessage: string }[] ) { ... } );

When the whenAllDone method is running and hits the following code, the arguments parameter is not right.

$.when.apply($, deferreds).then(function() {
    var failures = [];
    var successes = [];

    $.each(arguments, function(i, args) {
        // If we resolved with `true` as the first parameter
        // we have a failure, a success otherwise
        var target = args[0] ? failures : successes;
        var data = args[1];
        // Push either all arguments or the only one
        target.push(data.length === 1 ? data[0] : args);
    });

    if(failures.length) {
        return result.reject.apply(result, failures);
    }

    return result.resolve.apply(result, successes);
});

In the original answer's fiddle, the arguments was in the form of [ true|false, currentDeferredArguments ][]. Each element in the array, was the array of parameters resulting from currentDeferred.resolve(true|false, arguments);.

However, mine is a flattened array in the form of [ true|false, currentDeferredArguments ]. So when I loop the arguments in $.each(arguments, function (i, args) {, my args are never an 'array'. The first args is simply a boolean from the currentDeferred.resolve call, which then obviously screws up the logic in that loop.

If I change my code to simply test code the way he did (as in the following) it works as expected.

var dfd1 = $.Deferred();
var dfd2 = $.Deferred();

setTimeout(function () {
    console.log('Resolve dfd2');
    dfd2.reject( { "Options": currentOptions, "ErrorMessage": "Test 2" } );
}, 200);

setTimeout(function () {
    console.log('works dfd1');
    dfd1.reject( { "Options": currentOptions, "ErrorMessage": "Test 1" } );
}, 100);

$.whenAllDone( dfd1, dfd2 ).then(

So how can I correctly wrap my original call to submitCalculation to correctly return a deferred object so whenAllDone works?

解决方案

The problem was inside jquery's when method.

jquery.when: function( subordinate /* , ..., subordinateN */ ) { ...

It has a line like:

// If resolveValues consist of only a single Deferred, just use that.
deferred = remaining === 1 ? subordinate : jQuery.Deferred(),

And this changes the shape of the arguments, so I had to put it back to the common shape my code expects (i.e. the same shape when multiple deferreds are passed to whenAllDone)

const deferredArgs = jqueryWhenUsesSubordinate
    ? [[ arguments[ 0 ], arguments[ 1 ] ]]
    : arguments

$.each(deferredArgs, function (i, resolvedArgs) {
    var target = !resolvedArgs[0] ? failures : successes;
    var data = resolvedArgs[1];
    target.push(data.length === 1 ? data[0] : data);
});

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