fill()

Array.prototype.fill = function(value, start = 0, end = this.length) {
  // Handle negative values for start
  if (start < 0) {
    start += this.length;
    if (start < 0) start = 0;
  }
 
  // Handle negative values for end
  if (end < 0) {
    end += this.length;
  }
 
  // Ensure start is not greater than end
  if (start > end) {
    [start, end] = [end, start];
  }
 
  // Fill the array
  for (let i = start; i < end; i++) {
    this[i] = value;
  }
 
  return this;
};

扩展阅读

• Js中使用fill()进行数组填充的大坑，你遇到过吗？
• js数组怎么填充默认值