I want to make this code better , its works now, but i think it can be better , i have a hook and one property is onChange that get value and can setState and return that value for value of input , in the middle of code , i should check two regex and if is not valid skip the setState and return that .

    onChange: (value) => {
      const validRegex = /^[\u0600-\u06EF\s]+$/;
      if (!validRegex.test(value)) {
        const regex1 = /[a-zA-Z0-9]/g;
        const regex2 = /[\u06F0-\u06F9]+$/;
        return value.replace(regex1, '').replace(regex2, '');

      setData((prev) => ({
        name: value,
      return value;
<input value={data.name} onChange={(e) => onChange(e.target.value)} />

I replace , because i dont want miss text that user wrote. ,

example: value : This is name 1234 ===> result : This is name

  • 2
    \$\begingroup\$ I've given rewriting your title a shot to give you an idea of what we're looking for, feel free to improve it along those lines. \$\endgroup\$
    – Mast
    Jan 6, 2022 at 18:32
  • 2
    \$\begingroup\$ This code removes non-Unicode characters from a string, right? If so, perhaps that can be incorporated into the title \$\endgroup\$ Jan 6, 2022 at 18:54
  • \$\begingroup\$ yeah @peterSO, I want to deprive user just type arabic character , but because i want to to have previous character in the input , i should find that false character and replace with empty , otherwise in the middle string when user entered wrong character , the whole of string converted to empty suddenly \$\endgroup\$ Jan 7, 2022 at 19:10
  • \$\begingroup\$ @tmohammad78 Does your input field look like <input value={data.name} onChange={(e) => onChange(e.target.value)} />? If not, could you please add it to the question? \$\endgroup\$ Jan 10, 2022 at 17:49
  • \$\begingroup\$ @NikitaSkrebets, thank you for your attention \$\endgroup\$ Jan 10, 2022 at 18:58

1 Answer 1


Firstly, regular expression constants are better be placed outside of component function. Otherwise they get recreated each change event.

Second, is there a purpose of changing value? If we enter the if statement, we will not change the state, so it will affect nothing. And we don't need to return value; in the end, too.

Third, in current configuration there is no need to have regex2, because if we get a string \u0600\u06F0, which is a letter and a number (if I understand correctly), we will remove the number later. If it's \u06F0\u0600, a reversed one, we won't remove it. Though anyway, in the end it doesn't matter, because operations inside the if statement won't change the state.

Fourth, we check for /^[\u0600-\u06EF\s]+$/. Because of the + in the end we can't have an empty string. I don't know if it's by design, but if we have only 1 letter, we can't delete it, we can only select it and type another letter to replace it, which may not be convenient.

In the end, the version of code that I see fitting the task is:

  // arabic letters and signs without numbers
  const validRegex = /^[\u0600-\u06EF\s]+$/;

  const MyComponent = () => {

    // ...

    onChange: (value) => validRegex.test(value)
      && setData((prev) => ({ ...prev, name: value }));

  // ...


Please correct me if needed

  • 1
    \$\begingroup\$ Great answer. I would have only added that a regex should have a comment with what was intended \$\endgroup\$
    – konijn
    Jan 13, 2022 at 12:29
  • \$\begingroup\$ @konijn, thank you! Good point, added a comment. \$\endgroup\$ Jan 13, 2022 at 14:50

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