循环然后重置 node.js 中的数组

Posted 2023-03-08

【中文标题】循环然后重置 node.js 中的数组

【英文标题】：Loop through then reset an array in node.js

【发布时间】：2021-03-19 02:30:10

【问题描述】：

编辑：我尝试过类似的事情：

let firstarray = ["one", "two", "three", "four", "five", "six"]
let secondarray = ["1", "2", "3"]
let currentindex = 0;
if(currentindex == secondarray.length) 
currentindex - secondarry.length

firstarray.forEach(item => 
console.log(`$item $secondarray[currentindex]`)
currentindex++
);

这行得通吗？或者有什么类似的我可以做的吗？

简单解释：

//I have 2 arrays:
let firstarray = ["one", "two", "three", "four", "five", "six"]
let secondarray = ["1", "2", "3"]
//how can i log both of these but repeat through the second array as such:
"one 1"
"two 2"
"three 3"
"four 1"
"five 2"
"six 3"

不是那么简单的解释：

我想尝试反复循环遍历一个数组，例如：

let myarray = ["1", "2", "3"] //multiple strings

上面是我的数组，我知道如果我这样做：

console.log(myarray[0])

它返回 1，如果我这样做：

myarray.forEach(item => 
console.log(item)
);

它记录 1 然后 2 然后 3 但这取决于数组本身。

假设我有另一个包含 6 个项目的数组：

let firstarray = ["one", "two", "three", "four", "five", "six"]
let secondarray = ["1", "2", "3"]
 firstarray.forEach(item => 
console.log(`$item`)
);

这个日志：

one
two
three
four
five
six

我怎样才能让它记录并循环第二个数组，所以它返回这个：

"one 1"
"two 2"
"three 3"
"four 1"
"five 2"
"six 3"

【参考方案1】：

你可以使用第二个数组长度的模数...

firstarray.forEach((num, index) => 
    console.log(num + " " + secondarray[index % secondarray.length])
)

输出：

"one 1"
"two 2"
"three 3"
"four 1"
"five 2"
"six 3"

【讨论】：

所以我猜想将第二个值存储为变量然后：let secondvalue = secondarray[index % secondarray.length] 会工作吗？

【参考方案2】：

如果你想对任意 2 个数组做这个（不知道哪个更大）

//get the biggest array's length
var maxLen = Math.max(arr1.length, arr2.length);
for(var i = 0;i<maxLen;i++) 
    //get the elements mod the length to wrap around
    var ele1 = arr1[i % arr1.length];
    var ele2 = arr2[i % arr2.length];
    console.log(ele1 + " " + ele2);

【参考方案3】：

使用单个索引遍历两个数组，将该索引的剩余部分用于第二个数组。

let firstarray = ["one", "two", "three", "four", "five", "six"]
let secondarray = ["1", "2", "3"]
let index = -1
while (++index < firstarray.length) 
  console.log(firstarray[index], secondarray[index % secondarray.length])

【讨论】：

有没有办法在 foreach 内部严格执行此操作：let firstarray = ["one", "two", "three", "four", "five", "six"] let secondarray = ["1", "2", "3"] firstarray.forEach(item => //everything done here );

【参考方案4】：

我想通了！

let firstarray = ["one", "two", "three", "four", "five", "six"]
let secondarray = ["1", "2", "3"]
let currentindex = 0;
firstarray.forEach(item => 
console.log(`$item $secondarray[currentindex]`)
currentindex++
if(currentindex === secondarray.length) 
  currentindex -= secondarray.length

);

返回我想要的！