问题描述
我有这个函数,我必须返回/显示结果的值,我使用的是react native和couchDB,因为我的数据库在代码清单中。我已经尝试过了,但是没有用。请帮我解决这个问题。
vacant (room) {
localNoteDb
.find({
selector: {
status: "vacant",room_type: room
},fields: ['_id','room_type','room_no','price','status','user','updated_at','hour_status','price_per'],use_index: nameIndex_status.status,sort: [{status: 'asc'}]
})
.then(result => {
console.log('getListNoteFromDb',result)
let getLenght = result.doc
const results= Object.keys(result).length
console.log('value of results: ',results)
return(
<Text> {Object.keys(result).length}</Text>
);
})
}
解决方法
尝试这种方式
function Example() {
const [count,setCount] = useState(0);
// Similar to componentDidMount
useEffect(() => {
vacant(...);
});
const vacant (room) {
localNoteDb
.....
.....
.then(result => {
console.log('getListNoteFromDb',result)
let getLenght = result.doc
const results= Object.keys(result).length
setCount(results); <-- This way -->
});
}
return (
<Text> {count}</Text>
);
}