How do I programatically fill input field value with React?

Question

I have a modal with some input fields. I can easily pass the data automatically with the user typing an input, using onChange function in the input field, as

Answer 1

Use controlled component for this situation, define a value property of input element like this:

Whenever you will update that variable, automatically that value will get populated in input element.

Now you can populate some default value by assigning a value to variable_name and user can update that value by onChange function.

As per DOC:

An input form element whose value is controlled by React in this way is called a "controlled component".