💾arr.max()

💾 程式

💾 replit: arr.max()

Array.prototype.max = function() {
    return this.reduce((partialMax, nextValue) => Math.max(partialMax, nextValue));
};

💈範例：

[1,2,3].max(),    // 3
[4,2,3].max(),    // 4
// [].max(),      // ⛔ TypeError: Reduce of empty array with no initial value

🧨 雷區

雖然使用下列的語法也可以找出數列的最大值，但不能用於太大的陣列。

// both spread (...) and `apply` will either fail or return the wrong result 
// if the array has too many elements, because they try to pass the array 
// elements as function parameters. 
const arr = [1, 2, 3];
const max = Math.max(...arr);
const max = Math.max.apply(null, arr);

📘 手冊

• Math.max() ⟩ Getting the maximum element of an array

Untitled

• Is there a max number of arguments JavaScript functions can accept?