how to set useState as array react hooks code example
Example 1: how to set value in array react hook usestate
const[array,setArray]= useState([
{id: 1, value: "a string", othervalue: ""},
{id: 2, value: "another string", othervalue: ""},
{id: 3, value: "a string", othervalue: ""},
])
const updateItem =(id, whichvalue, newvalue)=> {
var index = array.findIndex(x=> x.id === id);
let g = array[index]
g[whichvalue] = newvalue
if (index === -1){
console.log('no match')
}
else
setArray([
...array.slice(0,index),
g,
...array.slice(index+1)
]
);
}
onPress={()=>updateItem(2,'value','ewfwf')}
onPress={()=>updateItem(1,'othervalue','ewfwf')}
Example 2: react setstate in hooks to array of objects value
const [datas, setDatas] = useState([
{
id: 1,
name: 'john',
gender: 'm'
}
{
id: 2,
name: 'mary',
gender: 'f'
}
]);
const updateFieldChanged = index => e => {
console.log('index: ' + index);
console.log('property name: '+ e.target.name);
let newArr = [...datas];
newArr[index] = e.target.value;
setDatas(newArr);
}
return (
<React.Fragment>
{ datas.map( (data, index) => {
<li key={data.name}>
<input type="text" name="name" value={data.name} onChange={updateFieldChanged(index)} />
</li>
})
}
</React.Fragment>
)