diff --git a/packages/fineui/src/core/constant/writable.var.js b/packages/fineui/src/core/constant/writable.var.js
index 3bca927e5..2b22ba030 100644
--- a/packages/fineui/src/core/constant/writable.var.js
+++ b/packages/fineui/src/core/constant/writable.var.js
@@ -14,7 +14,7 @@ export const setEventResponseTime = v => {
 PropertyDescriptors["EVENT_RESPONSE_TIME"] = {
     enumerable: true,
     configurable: true,
-    get: function () {
+    get: function() {
         return EVENT_RESPONSE_TIME;
     },
     set: setEventResponseTime,
@@ -27,7 +27,7 @@ export const setPixUnit = v => {
 PropertyDescriptors["pixUnit"] = {
     enumerable: true,
     configurable: true,
-    get: function () {
+    get: function() {
         return pixUnit;
     },
     set: setPixUnit,
@@ -40,7 +40,7 @@ export const setPixRatio = v => {
 PropertyDescriptors["pixRatio"] = {
     enumerable: true,
     configurable: true,
-    get: function () {
+    get: function() {
         return pixRatio;
     },
     set: setPixRatio,
@@ -48,12 +48,15 @@ PropertyDescriptors["pixRatio"] = {
 
 export let StartOfWeek = 1;
 export const setStartOfWeek = v => {
+    if (![0, 1].includes(v)) {
+        throw new Error("setStartOfWeek must be 0 or 1");
+    }
     StartOfWeek = v;
 };
 PropertyDescriptors["StartOfWeek"] = {
     enumerable: true,
     configurable: true,
-    get: function () {
+    get: function() {
         return StartOfWeek;
     },
     set: setStartOfWeek,
@@ -66,7 +69,7 @@ export const setBlankSplitChar = v => {
 PropertyDescriptors["BlankSplitChar"] = {
     enumerable: true,
     configurable: true,
-    get: function () {
+    get: function() {
         return BlankSplitChar;
     },
     set: setBlankSplitChar,
@@ -93,7 +96,7 @@ export const setPixFormat = v => {
 PropertyDescriptors["pixFormat"] = {
     enumerable: true,
     configurable: true,
-    get: function () {
+    get: function() {
         return pixFormat;
     },
     set: setPixFormat,
@@ -118,7 +121,7 @@ export let setToPix = v => {
 PropertyDescriptors["toPix"] = {
     enumerable: true,
     configurable: true,
-    get: function () {
+    get: function() {
         return toPix;
     },
     set: setToPix,
@@ -135,7 +138,7 @@ export const setEventBlur = v => {
 PropertyDescriptors["EVENT_BLUR"] = {
     enumerable: true,
     configurable: true,
-    get: function () {
+    get: function() {
         return EVENT_BLUR;
     },
     set: setEventBlur,