常用的JS函数整理

• ID生成器

/**
 * ID生成器
 * @param len 生成的ID的长度
 * @param radix 生成的ID的混淆器长度
 * @returns 
 */
export function generateId(len: number, radix: number) {
  var chars = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'.split('');
  var uuid = [],
    i;
  radix = radix || chars.length;

  if (len) {
    // Compact form
    for (i = 0; i < len; i++) uuid[i] = chars[0 | (Math.random() * radix)];
  } else {
    // rfc4122, version 4 form
    var r;

    // rfc4122 requires these characters
    uuid[8] = uuid[13] = uuid[18] = uuid[23] = '-';
    uuid[14] = '4';

    // Fill in random data.  At i==19 set the high bits of clock sequence as
    // per rfc4122, sec. 4.1.5
    for (i = 0; i < 36; i++) {
      if (!uuid[i]) {
        r = 0 | (Math.random() * 16);
        uuid[i] = chars[i == 19 ? (r & 0x3) | 0x8 : r];
      }
    }
  }

  return uuid.join('');
}