如何在多維數組中返回 boolean 之后的值？

Question

我試圖過濾多維數組以僅返回此數組中 boolean 之后的索引。

該數組中的第一個鍵需要像“Tafeblad model”和“Uitstraling”一樣留在數組中，以及布爾值后面的可選值

["Tafelblad model", true, "Rechthoekig", "Vierkant", "Ovaal / Rond / Overig"],
["Uitstraling", "Licht robuust", "Midden robuust", true, "Zwaar robuust", "Weinig", "Midden (standaard)", true, "Veel oneffenheden en scheuren"]`

新數組就像

["Tafelblad model", "Rechthoekig"],
["Uitstraling", "Zwaar robuust", "Veel oneffenheden en scheuren"]`

Answer 1

您可以關閉您設置的標志以保留您看到的下一個條目：

let flag = true; // We want the first one
const newArray = array.filter(entry => {
    const keep = flag;
    flag = typeof entry === "boolean";
    return keep;
});

現場示例：

 function example(array) { let flag = true; // We want the first one const newArray = array.filter(entry => { const keep = flag; flag = typeof entry === "boolean"; return keep; }); console.log(newArray); } example(["Tafelblad model", true, "Rechthoekig", "Vierkant", "Ovaal / Rond / Overig"]); example(["Uitstraling", "Licht robuust", "Midden robuust", true, "Zwaar robuust", "Weinig", "Midden (standaard)", true, "Veel oneffenheden en scheuren"]);

Answer 2

您可以為此使用.filter(..) function，這是一個示例：

 let arr1 = ["Tafelblad model", true, "Rechthoekig", "Vierkant", "Ovaal / Rond / Overig"]; let arr2 = ["Uitstraling", "Licht robuust", "Midden robuust", true, "Zwaar robuust", "Weinig", "Midden (standaard)", true, "Veel oneffenheden en scheuren"]; const filterFn = (value, index, arr) => { return index === 0 || arr[index - 1] === true; }; arr1 = arr1.filter(filterFn); arr2 = arr2.filter(filterFn); console.log(arr1); console.log(arr2);

傳遞給.filter(..)的回調 function 接收當前迭代的值、當前迭代的索引和原始數組作為參數。 filterFn function 中的條件檢查迭代的索引是否為0 （該值是數組中的第一個值）或前一項嚴格等於true

Answer 3

使用map()和filter()

 let arrays = [ ["Tafelblad model", true, "Rechthoekig", "Vierkant", "Ovaal / Rond / Overig"], ["Uitstraling", "Licht robuust", "Midden robuust", true, "Zwaar robuust", "Weinig", "Midden (standaard)", true, "Veel oneffenheden en scheuren"] ] let result = arrays.map(arr => { return arr.filter((v, i) => typeof arr[i - 1] === "boolean" || i == 0); }) console.log(result)