[問題] 同步變數接異步函數返回值
雖然這個問題有點蠢, 但是爬過相關文章都看不太懂. 目前是看到利用Promise
來解決, 但是找到的例子有點複雜不太能消化. 想請求大神幫忙.
舉個最簡單的例子 我今天想要做這樣的事情：
var x = getValue();
function getValue(){
var temp;
setTimeout(function(){temp = 3}, 2000);
return temp
}
這時候因為執行返回時 temp 還沒有被賦值, 所以x 會是undefined.
我該怎麼用promise 來讓我確定拿到我要得值才返回給 x 接住呢.
或者有其他技術可以實現. 不好意思, 初學js. 請指點迷津, 謝謝！
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