const DynPut: FC<Props> = Props => {
const [value, setValue] = useState<string>(['1', '2', '3', '4']);
return (
<View>
{value.map(v => {
<Text>{v}</Text>;
})}
</View>
);
};
無法在螢屏上獲取值 1-5。我正在使用打字稿并保存了帶有.tsx擴展名的檔案
uj5u.com熱心網友回復：
地圖的語法錯誤，請改用普通括號：
{value.map((v) => (
<Text>{v}</Text>
))}
uj5u.com熱心網友回復：
供參考
map() 期望回傳值，有多種可能，例如：
const data = [{ x: 55, y: 34 }, { x: 75, y: 12 }];
const result1 = data.map(d => d.x); // inline
const result2 = data.map(d => (
d.x // use round brackets
));
const result3 = data.map(d => {
return d.x; // use return statement
});
console.log(result1, result2, result3);如果你想在回傳值之前對資料做一些事情，最后一種方法很方便。
const data = [{ x: 55, y: 34 }, { x: 75, y: 12 }];
const result = data.map(d => {
const xTimesFive = d.x * 5; // do something with the x value
const dividedByTwo = xTimesFive / 2;
return dividedByTwo;
});
console.log(result);
// note, a simple calculation or check can also be done in the other methods
console.log(data.map(d => d.x > 60 ? "big" : "small"));轉載請註明出處，本文鏈接：https://www.uj5u.com/qianduan/373497.html
標籤：javascript 数组 打字稿 反应原生