使用ForEach循环递增的值应用于每个元素 [英] Incrementing value with a ForEach loop to apply on each element

问题描述

寻找有关数组和增量的帮助.

looking for help with arrays and increments.

我有一个函数，可以将相同的样式应用于数组中的每个新元素，如下所示.

I have a function which applies the same style to each new element in an array as you can see below.

function SnakeBodyLeft(){
  StorePositions.forEach(BodySnake => {
    BodySnake.style.gridRowStart = (Initial_y + y);
    BodySnake.style.gridColumnStart = (Initial_x + x)+1 ;
  });
};

// this results in

StorePositions[0] = BodySnake.style.gridColumnStart = (Initial_x + x)+1 
StorePositions[1] = BodySnake.style.gridColumnStart = (Initial_x + x)+1
StorePositions[2] = BodySnake.style.gridColumnStart = (Initial_x + x)+1

And so on...

我想编写一个函数，执行上面所示的操作，但是为每个新元素增加值+1，并为第一个元素保留初始值.结果可能是这样的:

I want to write a function that does what is shown above , but increments the value +1 for Each new element and keep the initial value for the first elements. The result would be somethink like :

StorePositions[0] = BodySnake.style.gridColumnStart = (Initial_x + x)+1 
StorePositions[1] = BodySnake.style.gridColumnStart = (Initial_x + x)+2
StorePositions[2] = BodySnake.style.gridColumnStart = (Initial_x + x)+3
StorePositions[3] = BodySnake.style.gridColumnStart = (Initial_x + x)+4

And so on....   

我试图使1称为i的变量并使之递增.但是，当我这样做时，i的增量将应用于数组中的所有元素，而不仅是新元素.

I have tried to make 1 a variable called i and increment it. But when I do this , the increment of i is applied to all elements in the array and not just the new elements.

let i = 1++;

function SnakeBodyLeft(){
  StorePositions.forEach(BodySnake=> {
    BodySnake.style.gridRowStart = (Initial_y + y);
    BodySnake.style.gridColumnStart = (Initial_x + x) + i ;
  });
};


//this results in the incremented value being applied to all elements , not just the new ones .

StorePositions[0] = BodySnake.style.gridColumnStart = (Initial_x + x)+1 
StorePositions[1] = BodySnake.style.gridColumnStart = (Initial_x + x)+1
StorePositions[2] = BodySnake.style.gridColumnStart = (Initial_x + x)+1

or

StorePositions[0] = BodySnake.style.gridColumnStart = (Initial_x + x)+2 
StorePositions[1] = BodySnake.style.gridColumnStart = (Initial_x + x)+2
StorePositions[2] = BodySnake.style.gridColumnStart = (Initial_x + x)+2

基本上，随着索引的增长(0,1,2,3 ...)，索引中每个新元素的值i也应增长(0,1,2,3 ...).

Basically , as the index grows(0,1,2,3...) , so should the value i in each new element in the index.(0,1,2,3...).

但是Iam有点卡住了！任何人都可以帮忙吗?

But Iam kinda stuck ! Anyone can help ?

推荐答案

尝试一下

function SnakeBodyLeft(){
  StorePositions.forEach((BodySnake, i)=> {
    BodySnake.style.gridRowStart = (Initial_y + y);
    BodySnake.style.gridColumnStart = (Initial_x + x) + i;
  });
};

更新如果您需要从1开始递增，请执行以下操作:

UPDATE If you need to start the increment from 1 then do this instead:

function SnakeBodyLeft(){
  StorePositions.forEach((BodySnake, i)=> {
    BodySnake.style.gridRowStart = (Initial_y + y);
    BodySnake.style.gridColumnStart = (Initial_x + x) + (i + 1);
  });
};

您可以为forEach添加一个索引，例如 forEach(element，index)=>{...}

You can add an index for the forEach like so forEach(element, index) => { ... }

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