javascript - Dynamically change the number of 'defer' calls in queue.js - Stack Overflow

admin管理员组

文章数量:1435796

My webpage lets the user plot multiple timeseries on a chart and I am using queue.js to go and asynchronously get this data, like so:

queue()
.defer(d3.json, "api/TransactionCost/?marketCode=" + marketCode1)
.defer(d3.json, "api/TransactionCost/?marketCode=" + marketCode2)
.defer(d3.json, "api/TransactionCost/?marketCode=" + marketCode3)
.await(onDataLoaded);

function onDataLoaded(error, json1, json2, json3) {
  // plot the 3 timeseries
}

I want the user to be able to request extra lines, if they wish, which will mean that I need to do extra 'defer' calls. I'd like to know how to dynamically append extra 'defer' calls (if it's possible) and also how to create the 'onDataLoaded' function so that it can handle a variable amount of parameters.

My webpage lets the user plot multiple timeseries on a chart and I am using queue.js to go and asynchronously get this data, like so:

queue()
.defer(d3.json, "api/TransactionCost/?marketCode=" + marketCode1)
.defer(d3.json, "api/TransactionCost/?marketCode=" + marketCode2)
.defer(d3.json, "api/TransactionCost/?marketCode=" + marketCode3)
.await(onDataLoaded);

function onDataLoaded(error, json1, json2, json3) {
  // plot the 3 timeseries
}

I want the user to be able to request extra lines, if they wish, which will mean that I need to do extra 'defer' calls. I'd like to know how to dynamically append extra 'defer' calls (if it's possible) and also how to create the 'onDataLoaded' function so that it can handle a variable amount of parameters.

• javascript
• queue.js

Share Improve this question Follow asked Feb 10, 2014 at 20:27 ninjaPixelninjaPixel 6,39244 gold badges3838 silver badges5050 bronze badges

Add a ment  | 

1 Answer 1

Sorted by: Reset to default 10

I'd like to know how to dynamically append extra 'defer' calls (if it's possible)

Use a variable for the queue, and dynamically append defer calls to it:

var q = queue();
for (/* each file */)
    q = q.defer(d3.json, filename);
q.await(onDataLoaded);

how to create the 'onDataLoaded' function so that it can handle a variable amount of parameters.

You can use the arguments object to access a variadic amount of parameters. In your case, it would look like

function onDataLoaded(error) {
    if (!error) {
        // Either simply loop them:
        for (var i=1; i<arguments.length; i++)
            … arguments[i] …
        // or slice them into an array:
        var jsons = Array.prototype.slice.call(arguments, 1);
        …
    } else { … }
}

本文标签： javascriptDynamically change the number of 39defer39 calls in queuejsStack Overflow