JavaScript 根据数据组合多个数组

Question

When type equals all, I need to combine two arrays into one. I have the code, but it gets the wrong result。

 const arr = [{value: 'aa'}, {value: 'bb'}]; const arr2 = [{type: 'all'}, {type: 'text', value: 'a2'}, {type: 'all'}] arr.forEach((item, index) => { arr2.forEach((items, indexs) => { if (items.type === 'all') { items.value = arr[index].value } }) }) console.log(arr2)

I hope to get this result

 arr2 = [{type: 'all', value: 'aa'}, {type: 'text', value: 'a2'}, {type: 'all', value: 'bb'}] console.log(arr2)

Answer 1

It's not a good idea to mutate the data that you're looping over.

If I understand correctly, you need to iterate through arr2 and intersperse items from arr when type is all .

I'd use Array.map for this sort of thing:

 const arr = [{value: 'aa'}, {value: 'bb'}]; const arr2 = [{type: 'all'}, {type: 'text', value: 'a2'}, {type: 'all'}] const combined = arr2.map(({type, ...rest})=>type==='all'?{type, ...arr.shift()}:{type, ...rest}) console.log(combined)