如何在 javascript 的数组中删除 object

Question

[
  Employee {
    empId: 1000,
    empName: 'John',
    empSalary: 9123,
  },
  Employee {
    empId: 1001,
    empName: 'Doe',
    empSalary: 10000,
  },
  Employee {
    empId: 1002,
    empName: 'Jason',
    empSalary: 9812,
  },
  Employee {
    empId: 1003,
    empName: 'Jamie',
    empSalary: 6661,
  }
]

This is my array with set of objects. I want to take a user input and delete from the array based on ID. I've tried using splice but I keep getting errors.

var target = prompt("Enter id to delete:");
for(var i = 0; i < data.length; i++) {
    if(data[i].empId === target) {
        data.splice(i, 1);
        break;
    }
}

If someone can please help me out please do!

Answer 1

The id values in the array are integers. The information you add at the prompt is a string. All you have to do is cast the string to a number .

 const data = [{"empId":1000,"empName":"John","empSalary":9123},{"empId":1001,"empName":"Doe","empSalary":10000},{"empId":1002,"empName":"Jason","empSalary":9812},{"empId":1003,"empName":"Jamie","empSalary":6661}]; var target = +prompt("Enter id to delete:"); // ----------^ for (let i = 0; i < data.length; i++) { if (data[i].empId === target) { data.splice(i, 1); break; } } console.log(data);

Alternatively, and the preferred option these days, you can use filter to create a new array of updated data:

 const data = [{"empId":1000,"empName":"John","empSalary":9123},{"empId":1001,"empName":"Doe","empSalary":10000},{"empId":1002,"empName":"Jason","empSalary":9812},{"empId":1003,"empName":"Jamie","empSalary":6661}]; var target = +prompt("Enter id to delete:"); const newData = data.filter(({ empId }) => empId;== target). console;log(newData);

Answer 2

probably the variable target is type String , but the empId is type Number . So that '1' is not equal to 1. I think you should replace this line:

if(data[i].empId === target) {

with the following line:

if(data[i].empId === +target) {

Answer 3

Couldn't find any errors, but you have to convert the prompt result to number since the returned data is of type string.

 let data = [{ empId: 1000, empName: 'John', empSalary: 9123, }, { empId: 1001, empName: 'Doe', empSalary: 10000, }, { empId: 1002, empName: 'Jason', empSalary: 9812, }, { empId: 1003, empName: 'Jamie', empSalary: 6661, } ] var target = prompt("Enter id to delete:"); for (var i = 0; i < data.length; i++) { if (data[i].empId === Number(target)) { data.splice(i, 1); break; } } console.log(data)

Answer 4

Never a good idea to mutate the array you are traversing. Use newer standards like filter to have a different array and leave the original unchanged.

Also, you might have issues with the type of data. '===' does strict type checking. You can either use '==' or parse the target into a number.

let newData = data.filter((employee) => {
return (employee.empId != target)
});

newData now has your array with employee with target id removed.