你好 filter() javascript 问题 clic 方法

Question

Hello everyone who knows the filter() method how I can tell if 2 or 3 values ​​are the same in an array of n removes only one with each click ex an array [1,2,3,1, 3,4,5,3,1,1,4] because with filter it will remove me every 1 or every 4 I would in fact like it to remove a 1 or a 4 for each click.

  var butonAll = document.querySelectorAll("#supprimer");
        console.log(butonAll);

        butonAll[i].addEventListener("click", function (e) {
          console.log("supprime moi");
          const id = e.target.getAttribute("data-id");

          objectJs2 = objectJs2.filter(function (obj, i) {
            console.log(obj, i);
            if (obj != id) return true;
          });
          objectJs = objectJs.filter(function (obj, i) {
            console.log(obj[0]._id, i);
            if (obj[0]._id != id) return true;
          });
          localStorage.setItem("object", JSON.stringify(objectJs));
          localStorage.setItem("id", JSON.stringify(objectJs2));
          console.log(id);
          console.log(objectJs.length);
          console.log(line2);
          location.href = "panier.html";
          if (objectJs.length === 0) {
            localStorage.clear();
          }
        });

Answer 1

Array#filter will takes a function as a parameter that is executed against every elements of the array, independently.

If you want to only filter the first matching element, you could use an external variable to keep track of it:

let matched = false
let filtered = array.filter(x => {
  if (matched) return true
  if (x.id == id) {
    matched = true
    return false
  }
  return true
})

An alternative approach would be to find the index to remove using either indexOf or findIndex and to remove it with splice

let index = array.indexOf(id);
array.splice(index, 1);

Answer 2

Maybe you want this.

 var arr = [1, 2, 3, 1, 3, 4, 5, 3, 1, 1, 4] console.log(arr); //Remove the first number one let has = arr.indexOf(1) //splice can remove data if receive negative numbers if (has > -1) arr.splice(has, 1) console.log(arr);