Organize elements within an array using TypeScript

Question

Organize elements within an array using TypeScript

I have an array that may contain multiple elements:

"coachID" : [ 
     "choice1", 
     "choice2"
]

If the user selects choice2, I want to rearrange the array like this:

"coachID" : [ 
     "choice2", 
     "choice1"
]

Similarly, if there are more than 2 elements in the array;

"coachID" : [ 
     "choice1", 
     "choice2",
     "choice3"
]

and the user chooses choice2, the array should be rearranged as follows:

"coachID" : [ 
     "choice2", 
     "choice1",
     "choice3"
]

Essentially, the selected element should always be positioned at the beginning of the array.

How can I implement this functionality using TypeScript?

typescript

Answer 1

Answer №1

There is no specific TypeScript requirement for this task.

To remove and then reinsert the selected element at the beginning of an array, you can utilize the splice() method to remove it and the unshift() method to add it back:

array.unshift(...array.splice(index, 1)); // index = index of the selected element

const data = [ 
     "choice1", 
     "choice2",
     "choice3"
];

const select = (array, i) => {
  if (array && array.length && i < array.length) {
    array.unshift(...array.splice(i, 1));
  }
};

console.log(data);

select(data, 1);

console.log(data);

If you wish to perform the operation based on the value of the selected element, you can use the indexOf() method:

array.unshift(...array.splice(array.indexOf(value), 1)); // value = selected value

const data = [ 
     "choice1", 
     "choice2",
     "choice3"
];

const select = (array, value) => {
  if (array && array.length) {
    const i = array.indexOf(value);
    
    if (i > 0) { 
      array.unshift(...array.splice(i, 1));
    }
  }
};

console.log(data);

select(data, "choice2");

console.log(data);

Answer 2

There is no specific TypeScript requirement for this task.

To remove and then reinsert the selected element at the beginning of an array, you can utilize the splice() method to remove it and the unshift() method to add it back:

array.unshift(...array.splice(index, 1)); // index = index of the selected element

const data = [ 
     "choice1", 
     "choice2",
     "choice3"
];

const select = (array, i) => {
  if (array && array.length && i < array.length) {
    array.unshift(...array.splice(i, 1));
  }
};

console.log(data);

select(data, 1);

console.log(data);

If you wish to perform the operation based on the value of the selected element, you can use the indexOf() method:

array.unshift(...array.splice(array.indexOf(value), 1)); // value = selected value

const data = [ 
     "choice1", 
     "choice2",
     "choice3"
];

const select = (array, value) => {
  if (array && array.length) {
    const i = array.indexOf(value);
    
    if (i > 0) { 
      array.unshift(...array.splice(i, 1));
    }
  }
};

console.log(data);

select(data, "choice2");

console.log(data);

Organize elements within an array using TypeScript

Answer №1

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