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JavaScript DOM Scripting By Example Improving the Application Code Next Steps

Brian McLaren
Brian McLaren
17,632 Points
Posted by Brian McLaren
Brian McLaren
17,632 Points

Form validation rejecting name duplicates 

I want to reject duplicate names from being added to the list or being appended to the dom.
form.addEventListener('submit', (e) => {
  const text = input.value;
  input.value = '';
  if (input.value) {
      alert('Please submit an entry');
    }
  else if (text !== text) {
    function removeDuplicates(text, prop) {
      return text.filter((obj, pos, arr) => {
      return arr.map(mapObj => mapObj[prop]).indexOf(obj[prop]) === pos;
  });
}
  } else {

      const li = createLI(text);
      ul.appendChild(li);
      e.preventDefault();
  }
});

1 Answer

Anjolaoluwa Akinremi
Anjolaoluwa Akinremi
8,532 Points
Anjolaoluwa Akinremi
Anjolaoluwa Akinremi
8,532 Points

form.addEventListener('submit', (e) => { //Preventing the browser's default behavior of submitting the form e.preventDefault();

//Storing the input value into a variable
const text = input.value;

if(input.value == ''){
  alert('Empty Name');
  return false;
}

//Resetting the input textbox to blank after submitting the form
input.value = '';



const li = createLI(text);
ul.appendChild(li);

});

Compare this to your code for filtering empty submissions