Sort array containing objects based on another array using _Underscore

arrays, javascript, underscore.js

Solution

Like this?

sorted = _.sortBy(Widgets, function(x) {
    return _.indexOf(sortArray, x[0].Id)
})

This is not very efficient, a faster way is to convert `sortArray` to an object `key=>index` and use hash lookups in `sortBy`:

sortObj = _.invert(_.object(_.pairs(sortArray)));

sorted = _.sortBy(Widgets, function(x) {
    return sortObj[x[0].Id]
})

Problem

I already read the previous questions answered, but it didn't fit with my need. I have an array of objects such as ``` var Widgets = [ [{Id: 'abcdef', post_id: 12345}], [{Id: 'ghijkl', post_id: 45678}], [{Id: 'mnoptq', post_id: 90123}] ]; ``` I have a second array : ``` var sortArray = ['ghijkl', 'mnoptq', 'abcdef']; ``` I need To reorder Widgets with the initial order of elements which appears on sortArray i've succeed to do it this way ``` sortArray.forEach(function(Id) { var found = false; Widgets = Widgets.filter(function(Widget) { if(!found && Widget.Id == Id) { NewWidgets.push(Widget); found = true; return false; } else { return true; } }); }); ``` But I wish to improve this code by using _SortBy but I didn't succeed so far... Anyhelp ? Edit Final result should be ``` var Widgets = [ [{Id: 'ghijkl', post_id: 45678}], [{Id: 'mnoptq', post_id: 90123}], [{Id: 'abcdef', post_id: 12345}] ]; ```

Original source