Why the array returning empty spaces

Question

It should be returning 9-12,1-4,5-8,9-11 but instead it's returning 9-12,1-4,5-8,9-11,,,,

var arr = [{
    Sanju: '9-12'
  }, {
    Sanju: '1-4'
  }, {
    Sanju: '5-8'
  }, {
    Sanju: '9-11'
  },
  {
    IRONMAN: '9-12'
  }, {
    VIVEGAM: '1-4'
  }, {
    VIVEGAM: '5-8'
  }, {
    VIVEGAM: '9-11'
  }
];

var b = Array.from(arr, x => x.Sanju);
document.write(b);
document.write(Array.isArray(b));

so how to get rid of this **,** and get only **Sanju Object** objects — Stone, Jul 11 '18 at 09:44
use `arr.filter(i=> i.Sanju);`. well, I've added that as an answer too — Muhammad Usman, Jul 11 '18 at 09:48

score 4 · Accepted Answer · answered Jul 11 '18 at 09:45

Since not all values in arr contains Sanju, some of the values will give you undefined when you return x.Sanju You can use filter to remove those like

var arr = [{Sanju: '9-12'},{Sanju: '1-4'}, {Sanju: '5-8'},{Sanju: '9-11'},
  {IRONMAN: '9-12'},{VIVEGAM: '1-4'}, {VIVEGAM: '5-8'},{VIVEGAM: '9-11'}
];
 
 var b= Array.from(arr, x => x.Sanju).filter(Boolean);
    document.write(b);
    document.write(Array.isArray(b));

Check Removing undefined values from Array for more details on how .filter(Boolean) works

score 4 · Answer 2 · answered Jul 11 '18 at 09:46

It should be returning 9-12,1-4,5-8,9-11 but instead it's returning 9-12,1-4,5-8,9-11,,,,

Coz there is no Sanju property on some of the objects. You should first filter you array and then do the rest

var arr = [{
    Sanju: '9-12'
  }, {
    Sanju: '1-4'
  }, {
    Sanju: '5-8'
  }, {
    Sanju: '9-11'
  },
  {
    IRONMAN: '9-12'
  }, {
    VIVEGAM: '1-4'
  }, {
    VIVEGAM: '5-8'
  }, {
    VIVEGAM: '9-11'
  }
];

var o = arr.filter(i=> i.Sanju);

var b = Array.from(o, x => x.Sanju);
document.write(b);
 
document.write(Array.isArray(b));

Why the array returning empty spaces

2 Answers2