const array = [{
id: "U",
T: "001"
},
{
id: "R",
T: "002"
},
{
id: "U",
T: "003"
},
{
id: "R",
T: "004"
},
{
id: "U",
T: "005"
},
]
Above array can have multiple objects with id: 'R' and i want to ignore all objects that are before id: 'R'.
Expected:
const array = [
{ id: "U",
T: "005"}]
Can someone please help with this
Array#map, get the list of idsArray#lastIndexOf, get the index of the last occurrence of the id "R"Array#splice, get the target sub-array following this indexconst array = [ { id: "U", T: "001" }, { id: "R", T: "002" }, { id: "U", T: "003" }, { id: "R", T: "004" }, { id: "U", T: "005" } ];
const ids = array.map(({ id }) => id);
const index = ids.lastIndexOf("R") + 1;
const res = array.splice(index);
console.log(res);Agree with all the above answers, but why do we go with the map, slice, reverese and all. We can simply use just a loop instead of those as below. Considering time as well, if the array length increases the combination of any of the map, reverse, slice, splice takes much time
const array = [{
id: "U",
T: "001"
},
{
id: "R",
T: "002"
},
{
id: "U",
T: "003"
},
{
id: "R",
T: "004"
},
{
id: "U",
T: "005"
},
];
let newArr = [];
for(let i = array.length - 1; i >= 0; i--){
if(array[i].id === 'R') break;
else newArr.push(array[i])
}
console.log(newArr);Reverse array, Find the index of first R, slice array...
const array = [{
id: "U",
T: "001"
},
{
id: "R",
T: "002"
},
{
id: "U",
T: "003"
},
{
id: "R",
T: "004"
},
{
id: "U",
T: "005"
}
]
const cheak = (element) => element.id === "R"
console.log(array.reverse().slice(0, array.findIndex(cheak)).reverse());