diff --git a/utils.js b/utils.js
index bb95454..220479f 100644
--- a/utils.js
+++ b/utils.js
@@ -281,6 +281,31 @@ function randItemByWeight(list, fieldName) {
   return ret;
 }
 
+
+function mapToArray(mapObj) {
+  const result = [];
+  mapObj.forEach((val, key) => {
+    result.push(val);
+  });
+  return result;
+}
+
+function mapToObject(mapObj) {
+  const result = {};
+  mapObj.forEach((val, key) => {
+    result[key] = val;
+  });
+  return result;
+}
+
+async function serial(obj, cb) {
+  let i = 0;
+  const arr = obj instanceof Map ? mapToArray(obj) : obj;
+  for (let val of arr) {
+    await cb(val, i++);
+  }
+}
+
 exports.rspErr = rspErr;
 exports.rspOk = rspOk;
 exports.rspData = rspData;
@@ -316,3 +341,6 @@ exports.excelToJson = excelToJson;
 exports.getArgv = getArgv;
 exports.hasKey = hasKey;
 exports.isPureNumberStr = isPureNumberStr;
+exports.serial = serial;
+exports.mapToArray = mapToArray;
+exports.mapToObject = mapToObject;