I want to fill the inputs value of a form with default values once the modal is opened
I did it with pure javascript using document.getElementById(textId).value='some value
as follow:
for(var i=0; i<details_data.length;i++){
let textId='text'+i;
let amountId='amount'+i;
document.getElementById(textId).value=details_data[i].text
}
This worked fine. but I want to know how to do it with React since I don't believe this is a best practice.
what i tried is to set the input value like this:
<input name='text' id={textId} value={el.text} onChange={details_handler.bind(index)}/>
But this woudn't let me change the value of the input. it just set the default value, and when i type in the input the value woudn't change as I want.
This is my code
const [details_data,set_details_data]=useState([
{'text':'','amount':''}
])
// called this function on `onChange` and store the data in `details_data`
function details_handler(e){
let name=e.target.name;
let value=e.target.value;
details_data[this][name]=value;
set_details_data(details_data);
}
JSX:
(In my case user can add inputs as many as he wants,That's why I put the inputs in a the mapping loop)
{
details_data.map((el,index) => {
let textId='text'+index;
let amountId='amount'+index;
return (
<div key={index}>
<input name='text' id={textId} value={el.text} onChange={details_handler.bind(index)}/>
<input name='amount' id={amountId} onChange={details_handler.bind(index)}/>
</div>
);
})
}
useEffect(() => {
if(detailsProps) {
set_details_data(detailsProps);
}
}, [detailsProps])
where your detailsProps (data from the api) will look something like this
detailsProps = [
{'text':'text1','amount':'100'},
{'text':'text2','amount':'200'}
]
onChange Function
const details_handler = (event, index) => {
const items = [...details_data];
items[index][event.target.name] = event.target.value;
set_details_data(items);
}
your view
{
details_data.map((el,index) => {
return (
<div key={index}>
<input name='text' value={el.text} onChange={(e) => details_handler(e, index)}/>
<input name='amount' value={el.amount} onChange={(e) => details_handler(e, index)}/>
</div>
);
})
}