我如何从递归$ .each对象中删除元素？

Question

For example, i have this data object:

var data = {
    'some': [
        {'id': 10, 'info': [{'next': 11}, {'next': 0}, {'next': 0},  {'next':  0}]}, 
        {'id': 11, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next':  0}]}, 
        {'id': 12, 'info': [{'next': 0},  {'next': 0}, {'next': 20}, {'next':  0}]}, 
        {'id': 13, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next':  0}]}, 
        {'id': 14, 'info': [{'next': 12}, {'next': 0}, {'next': 0},  {'next':  0}]}, 
        {'id': 15, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next':  0}]}, 
        {'id': 16, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next': 14}]}, 
        {'id': 17, 'info': [{'next': 0},  {'next': 0}, {'next': 13}, {'next':  0}]}, 
        {'id': 18, 'info': [{'next': 15}, {'next': 0}, {'next': 0},  {'next':  0}]}, 
        {'id': 19, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next':  0}]}, 
        {'id': 19, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next': 11}]}, 
        {'id': 20, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next':  0}]}
    ]
};

I want delete all elements with id where contains in next , for example, from data object above, i want get something like this

    var data = {
        'some': [
            {'id': 10, 'info': [{'next': 11}, {'next': 0}, {'next': 0},  {'next':  0}]}, 
            {'id': 16, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next': 14}]}, 
            {'id': 17, 'info': [{'next': 0},  {'next': 0}, {'next': 13}, {'next':  0}]}, 
            {'id': 18, 'info': [{'next': 15}, {'next': 0}, {'next': 0},  {'next':  0}]}, 
            {'id': 19, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next':  0}]}, 
            {'id': 19, 'info': [{'next': 0},  {'next': 0}, {'next': 0},  {'next': 11}]}, 
        ]
    };

I write this script, but it return Uncaught TypeError: Cannot read property 'id' of undefined , why?

var cleanData = function (d

ata) {
    $.each(data['some'], function (_is, some) {
        $.each(some['info'], function (_in, next) {
            if (next['next']) 
                $.each(data['some'], function (_is2, some2) {
                    if (some2['id'] == next['next']) 
                        data['some'].remove(_is2);
                });
        });
    });

    return data;
};

My example on JsFiddle.

Thanks.

Answer 1

UPDATE: See Andrew's answer on this page. It's a much cleaner and safer solution.

In short, you can't. You'll have to use a regular for loop with an index, instead, so that you can keep up with the new length of your array.

$.each(data['some'], function (_is, some) {
    $.each(some['info'], function (_in, next) {
        if (next['next']) 
            for(var i=0, len=data['some'].length; i < len; i++) {
                var some2 = data['some'][i];
                if (some2['id'] == next['next']) {
                    data['some'].remove(_is2);
                    // Decrement i since the next item will now be in the place of the one you removed.
                    i--;
                    // Decrement len since your array now holds one less item.
                    len--;
                }
            }
        }
    });
});

Answer 2

Array.prototype.filter is great for a problem like this. This code should produce what you're looking for:

data.some = data.some.filter(function(item) {
    return item.info.filter(function(i) {
        return i.next > 0;
    }).length > 0;
});

Answer 3

You can create this in two steps: First find all the IDs that are contained in any next object. Then filter the array and remove the rows with that IDs.

Example:

// Build ids table
var idsToRemove = data.some.reduce(function(ids, row) {
  return row.info.reduce(function(ids, obj) {
    return ids[obj.next] = true, ids;
  }, ids);
}, {});

// Filter out rows with those IDs
data.some = data.some.filter(function(row) {
  return !idsToRemove[row.id];
});

console.log(data);

 var data = { 'some': [ {'id': 10, 'info': [{'next': 11}, {'next': 0}, {'next': 0}, {'next': 0}]}, {'id': 11, 'info': [{'next': 0}, {'next': 0}, {'next': 0}, {'next': 0}]}, {'id': 12, 'info': [{'next': 0}, {'next': 0}, {'next': 20}, {'next': 0}]}, {'id': 13, 'info': [{'next': 0}, {'next': 0}, {'next': 0}, {'next': 0}]}, {'id': 14, 'info': [{'next': 12}, {'next': 0}, {'next': 0}, {'next': 0}]}, {'id': 15, 'info': [{'next': 0}, {'next': 0}, {'next': 0}, {'next': 0}]}, {'id': 16, 'info': [{'next': 0}, {'next': 0}, {'next': 0}, {'next': 14}]}, {'id': 17, 'info': [{'next': 0}, {'next': 0}, {'next': 13}, {'next': 0}]}, {'id': 18, 'info': [{'next': 15}, {'next': 0}, {'next': 0}, {'next': 0}]}, {'id': 19, 'info': [{'next': 0}, {'next': 0}, {'next': 0}, {'next': 0}]}, {'id': 19, 'info': [{'next': 0}, {'next': 0}, {'next': 0}, {'next': 11}]}, {'id': 20, 'info': [{'next': 0}, {'next': 0}, {'next': 0}, {'next': 0}]} ] }; // Build ids table var ids = data.some.reduce(function(ids, row) { return row.info.reduce(function(ids, obj) { return ids[obj.next] = true, ids; }, ids); }, {}); // Filter out rows with those IDs data.some = data.some.filter(function(row) { return !ids[row.id]; }); console.log(data); 

Answer 4

使用for时长大于零并从数组中删除索引一

Answer 5

The error you're getting is because not every object in the array has a property with a key of 'id'

I'm not exactly clear on what is supposed to be removed, but if it's everything that's first key is 'next, change this:

if (some2['id'] == next['next']) 

to this:

if (some2[0] == 'next') 

Working Demo

HTH,

-Ted