I am looking for a way to filter my JavaScript Array() columns where the parentId is equal to a variable passed into the method.
// Array decleration
var columns = []; // Columns
//...
for (var i1 in columns) {
if (columns[i1].parentId == listItem) {
//...
Could anybody recommend the easiest way to filter this using either plain JavaScript or jQuery to avoid using the if statement as shown above?
var filteredColumns = columns.filter(function(column) {
return column.parentId == listItem;
});
grep?
callback is invoked with three arguments: (1) the value of the element, (2) the index of the element, (3) the Array object being traversed"array = [1,2,3,4,5];
result = $.grep(array, function(n,i) {
return n > 3;
});
This will return an array of filtered elements where the results are greater than 3. Here n is the element in consideration, and i the index of the element. So as per your requirement, the code can run like this:
resultArray = $.grep(columns,function(n,i) {
return n == parentId;
});
Use ES5 Array's filter method:
var filtered = columns.filter(function (item) {
return item.parentId === listItem
});
In the link above there is also a shim for old browsers.
You can also doing that manually:
var filtered = [];
for (var i = 0, item; item = columns[i++];)
if (item.parentId === listItem) filtered.push(item);
