如何将嵌套数组转换为对象数组？

Hey there! Let's get your array conversion working properly. I've looked at your code and spotted a few small issues that are keeping it from working as expected—let's break them down and fix them step by step.

First, let's go over the problems in your original code: #

• Spelling mistake: You wrote array.lenght instead of array.length (missing a t). This would cause your loop to behave unpredictably.
• Incorrect loop boundary: Using i <= array.length will make your loop run one too many times (since array indices start at 0, the last valid index is array.length - 1). This would lead to trying to access array[i] when i equals the array length, which is undefined.
• Resetting the result array: You declare var res = [] inside the loop, which means it gets emptied every time the loop runs. By the end, you'd only have the last element in the array.
• Not creating the target object: You're pushing the original sub-array into res instead of converting it to the {id: ..., score: ...} format you need.

Here's the fixed version using a for loop: #

const array = [[1, 698],[32, 798],[69, 830],[95, 500]];
const res = []; // Declare the result array once, outside the loop

for(let i = 0; i < array.length; i++){ // Fixed spelling and loop condition
  const obj = {
    id: array[i][0], // Grab the first element of the sub-array as id
    score: array[i][1] // Grab the second element as score
  };
  res.push(obj); // Add the new object to the result array
}

console.log(res);
// Output: [{id:1, score:698}, {id:32, score:798}, {id:69, score:830}, {id:95, score:500}]

Even better: Use Array.map() for a cleaner solution #

Since you're transforming every element of the array into a new format, JavaScript's map() method is perfect for this—it's designed exactly for this kind of array-to-array transformation, and it's more concise:

const array = [[1, 698],[32, 798],[69, 830],[95, 500]];
const res = array.map(item => ({
  id: item[0],
  score: item[1]
}));

console.log(res);
// Same desired output as above

map() iterates over each element in the original array, runs your callback function on it, and collects all the returned values into a new array—no need to manually manage a loop counter or push to a result array.

内容的提问来源于stack exchange，提问作者arkahn jihu