Remove empty strings from array while keeping record Without Loop?

114,081

Solution 1

var arr = ["I", "am", "", "still", "here", "", "man"]
// arr = ["I", "am", "", "still", "here", "", "man"]
arr = arr.filter(Boolean)
// arr = ["I", "am", "still", "here", "man"]

filter documentation


// arr = ["I", "am", "", "still", "here", "", "man"]
arr = arr.filter(v=>v!='');
// arr = ["I", "am", "still", "here", "man"]

Arrow functions documentation

Solution 2

var newArray = oldArray.filter(function(v){return v!==''});

Solution 3

PLEASE NOTE: The documentation says:

filter is a JavaScript extension to the ECMA-262 standard; as such it may not be present in other implementations of the standard. You can work around this by inserting the following code at the beginning of your scripts, allowing use of filter in ECMA-262 implementations which do not natively support it. This algorithm is exactly the one specified in ECMA-262, 5th edition, assuming that fn.call evaluates to the original value of Function.prototype.call, and that Array.prototype.push has its original value.

So, to avoid some heartache, you may have to add this code to your script At the beginning.

if (!Array.prototype.filter) {
  Array.prototype.filter = function (fn, context) {
    var i,
        value,
        result = [],
        length;
        if (!this || typeof fn !== 'function' || (fn instanceof RegExp)) {
          throw new TypeError();
        }
        length = this.length;
        for (i = 0; i < length; i++) {
          if (this.hasOwnProperty(i)) {
            value = this[i];
            if (fn.call(context, value, i, this)) {
              result.push(value);
            }
          }
        }
    return result;
  };
}

Solution 4

arr = arr.filter(v => v);

as returned v is implicity converted to truthy

Solution 5

If are using jQuery, grep may be useful:


var arr = [ a, b, c, , e, f, , g, h ];

arr = jQuery.grep(arr, function(n){ return (n); });

arr is now [ a, b, c, d, e, f, g];

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Updated on July 08, 2022

Comments

  • Universal Grasp
    Universal Grasp almost 2 years

    This question was asked here: Remove empty strings from array while keeping record of indexes with non empty strings

    If you'd notice the given as @Baz layed it out;

    "I", "am", "", "still", "here", "", "man"
    

    "and from this I wish to produce the following two arrays:"

    "I", "am", "still", "here", "man"
    

    All the Answers to this question referred to a form of looping.

    My question: Is there a possibility to remove all indexes with empty string without any looping? ... is there any other alternative apart from iterating the array?

    May be some regex or some jQuery that we are not aware of?

    All answers or suggestions are highly appreciated.