javascript forEach 多函數數組

Question

我有源代碼，如何僅輸出 forEach arrise.tester2 或 JSON stringify？
這是代碼：

var arrise = [{"tester1":"testo","tester2":["testi1","testi2"]},{"tester1":"testc","tester2":["test1","test2"]},{"tester1":"testd","tester3":["tes1","tes3"]}];  

Answer 1

您可以使用array#map和array#filter 。 訪問數組中的每個對象並檢查tester2鍵。

 var arrise = [{"tester1":"testo","tester2":["testi1","testi2"]},{"tester1":"testc","tester2":["test1","test2"]},{"tester1":"testd","tester3":["tes1","tes3"]}]; var result = arrise .map(o => o.tester2) .filter(x => x); console.log(result);

Answer 2

您可以首先通過檢查屬性進行過濾，然后映射值。

 var arrise = [{ tester1: "testo", tester2: ["testi1", "testi2"] },{ tester1: "testc", tester2: ["test1", "test2"] }, { tester1: "testd", tester3:["tes1", "tes3"] }], tester2 = arrise .filter(o => o.tester2) .map(o => o.tester2); console.log(tester2);