Got it, let's break down what's going wrong and how to build the array structure you want.

Why the "Unexpected identifier" Error Happens #

That error pops up because you tried using a key: value syntax (like test44: { ... }) directly inside an array literal. Arrays in JavaScript are ordered collections of values—not key-value pairs (that's what objects are for). When you write test44: { ... } inside [], JavaScript doesn't recognize it as valid array syntax, hence the identifier error.

Two Correct Ways to Build Your Array #

Here are two straightforward approaches to create an array with an object at index 0, plus another object at a specific index (like 44):

1. Direct Index Assignment (Simplest & Most Common)

Just initialize an empty array, then assign objects to the exact indices you want. This works even if the indices are non-consecutive (JavaScript will fill the gaps with empty slots, which are harmless for most use cases):

// Start with an empty array
const myArray = [];

// Add object to index 0
myArray[0] = {
  name: "test0",
  data: "sample data for index 0"
};

// Add object to index 44
myArray[44] = {
  name: "test44",
  data: "sample data for index 44"
};

2. Pre-Fill to Avoid Sparse Arrays (Optional)

If you don't want empty slots between your indices, pre-fill the array with a placeholder (like undefined) first, then replace the target indices:

// Create an array of length 45 (indices 0-44) filled with undefined
const myArray = Array(45).fill(undefined);

// Replace index 0 with your object
myArray[0] = { name: "test0", data: "index 0 content" };

// Replace index 44 with your object
myArray[44] = { name: "test44", data: "index 44 content" };

Quick Note #

If your target index is stored in a variable (e.g., const targetIndex = 44), you can still use the same syntax: myArray[targetIndex] = { ... }—it works for static and dynamic indices alike.

内容的提问来源于stack exchange，提问作者user1234