⛺️第2期第2题：实现一个padStart()或padEnd()的polyfill

[lindaidai]

⛺️第2期第2题：实现一个padStart()或padEnd()的polyfill

[laibao101]

我来交作业了

String.prototype.myPadStart = function(targetLen, padString = " ") {
  if (!targetLen) {
    throw new Error("请传入需要填充的长度");
  }
  const padStrLen = padString.length;
  if (!padStrLen) return this;

  const originLen = this.length;
  const prefixLen = Math.max(0, targetLen - originLen);
  const repeatTimes = Math.ceil(prefixLen / padStrLen);
  return `${padString.repeat(repeatTimes).substring(0, prefixLen)}${this}`;
};

[LinDaiDai]

我来交作业了

String.prototype.myPadStart = function(targetLen, padString = " ") {
  if (!targetLen) {
    throw new Error("请传入需要填充的长度");
  }
  const padStrLen = padString.length;
  if (!padStrLen) return this;

  const originLen = this.length;
  const prefixLen = Math.max(0, targetLen - originLen);
  const repeatTimes = Math.ceil(prefixLen / padStrLen);
  return `${padString.repeat(repeatTimes).substring(0, prefixLen)}${this}`;
};

哈哈哈，比我的要简洁很多，棒