nodejs 十六进制字符串型数据与btye型数据相互转换

/**
 * byte型转换十六进制
 * @param b
 * @returns {string}
 * @constructor
 */
const Bytes2HexString = (b)=> {
 let hexs = "";
 for (let i = 0; i < b.length; i++) {
 let hex = (b[i]).toString(16);
 if (hex.length === 1) {
 hexs = '0' + hex;
 }
 hexs += hex.toUpperCase();
 }
 return hexs;
}

/**
 * 十六进制转换btye型
 * @param str
 * @returns {Promise}
 */
const Hexstring2btye = (str)=> {
 let pos = 0;
 let len = str.length;
 if (len % 2 != 0) {
 return null;
 }
 len /= 2;
 let hexA = new Array();
 for (let i = 0; i < len; i++) {
 let s = str.substr(pos, 2);
 let v = parseInt(s, 16);
 hexA.push(v);
 pos += 2;
 }
 return hexA;
}