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Extending the native Array prototype CodejavascriptArray.prototype.clean = function(deleteValue) {
for (var i = 0; i < this.length; i++) {
if (this[i] == deleteValue) {
this.splice(i, 1);
i--;
}
}
return this;
};
Usage
javascripttest = new Array("","One","Two","", "Three","","Four").clean("");
test2 = [1,2,,3,,3,,,,,,4,,4,,5,,6,,,,];
test2.clean(undefined);
Pure Javascript
Description
You can simply push the existing elements into other array (the example removes every "falsy" value: undefined, null, 0, false, NaN and "").
Codejavascriptfunction cleanArray(actual){
var newArray = new Array();
for(var i = 0; i
Usage
javascript
var result = cleanArray([1,2,,3,,3,,,,,,4,,4,,5,,6,,,,]);
Simple
Description
If you"ve got Javascript 1.6 or later you can use Array.filter using a trivial return true callback function.
Since .filter automatically skips missing elements in the original array.
The MDN page linked above also contains a nice error-checking version of filter that can be used in JavaScript interpreters that don"t support the official version.
Note that this will not remove null entries nor entries with an explicit undefined value, but the OP specifically requested "missing" entries.
Codejavascriptarr = arr.filter(function() {
return true;
});
javascriptarr = arr.filter(function(n) {
return n != undefined;
});
javascript// only for arrays items which are numbers is numbers strings arr = arr.filter(Number)
javascript[1, false, "", undefined, 2].filter(Boolean); // [1, 2]
javascript// only for single array items of type text
["","1","2",3,,"4",,undefined,,,"5"].join("").split("");
JQuery
Code
javascriptarr = $.grep(arr, function(n){
return n;
});
Underscope
Code
javascript_.filter([1, false, "", undefined, 2], Boolean); // [1, 2]
javascript_.compact([1, false, "", undefined, 2]); // [1, 2]Cool Way Description
Using ES6. IE support for filter is IE9 standards mode.
Codejavascriptvar arr = [1,2,null, undefined,3,,3,,,0,,,4,,4,,5,,6,,,,];
var temp = [];
for(let i of arr) {
// copy each non-empty value to the "temp" array
i && temp.push(i);
}
arr = temp;
delete temp; // discard the variable
arr // [1, 2, 3, 3, 4, 4, 5, 6]
Iteration
Code
javascriptvar arr = [1,2,null, undefined,3,,3,,,0,,,[],,{},,5,,6,,,,];
var len = arr.length, i;
for(i = 0; i < len; i++ ) {
// copy non-empty values to the end of the array
arr[i] && arr.push(arr[i]);
}
// cut the array and leave only the non-empty values
arr.splice(0 , len);
arr // [1,2,3,3,[],Object{},5,6]
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