字符串转十六进制

字符串转十六进制的步骤
将字符串的每一个元素转成十六进制再拼接在一起

 //转16进制
    stringToHex (str) {
      if (str === "")
        return "";
      var hexCharCode = [];
      hexCharCode.push("0x");
      for (var i = 0; i < str.length; i++) {
        hexCharCode.push((str.charCodeAt(i)).toString(16));
      }
      return hexCharCode.join("");
    },

    // 16进制转回字符串
    hexToString (hexCharCodeStr) {
      var trimedStr = hexCharCodeStr.trim();
      var rawStr =
        trimedStr.substr(0, 2).toLowerCase() === "0x"
          ?
          trimedStr.substr(2)
          :
          trimedStr;
      var len = rawStr.length;
      if (len % 2 !== 0) {
        alert("非法格式的ASCII码!");
        return "";
      }
      var curCharCode;
      var resultStr = [];
      for (var i = 0; i < len; i = i + 2) {
        curCharCode = parseInt(rawStr.substr(i, 2), 16); // ASCII Code Value
        resultStr.push(String.fromCharCode(curCharCode));
      }
      return resultStr.join("");
    },