How can I count all objects in an array that match a condition: is_read == true?
This is how my array looks like:
[
{
id: 1,
is_read: true,
},
{
id: 2,
is_read: true,
},
{
id: 3,
is_read: false,
},
{
id: 4,
is_read: true,
},
]
Just use filter method by passing a callback function and use length property applied for the result of filtering.
let data = [ { id: 1, is_read: true, }, { id: 2, is_read: true, }, { id: 3, is_read: false, }, { id: 4, is_read: true, }, ],
length = data.filter(function(item){
return item.is_read;
}).length;
console.log(length);You can also use a lambda expression.
let data = [ { id: 1, is_read: true, }, { id: 2, is_read: true, }, { id: 3, is_read: false, }, { id: 4, is_read: true, }, ],
length = data.filter(d => d.is_read).length;
console.log(length);
