Use the following code to update form fields with OnChange().

1. Declare the variable

    const [form, setForm] = useState(
        {
            mytextarea: { type: "textarea", title: "Your Name", name: "name", value: "This is the text area default value" },
        }
    );

 

2. Use the varilable in JSX - Call on the generateField() function whe OnChange to update form.mytextarea.value

{
                return <textarea
                    className="form-control"
                    rows={4}
                    cols={40}
                    name={form[fieldName].name}
                    onChange={(e) => setForm(
                        { ...form, mytextarea : {
                            ...form.mytextarea,
                                value: e.target.value
                        }
                    })}
                >{form[fieldName].value}</textarea>
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