diff --git a/zh-cn/application-dev/device/inputdevice-guidelines.md b/zh-cn/application-dev/device/inputdevice-guidelines.md
index d7aaf54eec4457c45bcf9d10a23d512cde768a29..d08fbacfef9c363dfb8b4c206008b05793e5434e 100644
--- a/zh-cn/application-dev/device/inputdevice-guidelines.md
+++ b/zh-cn/application-dev/device/inputdevice-guidelines.md
@@ -41,7 +41,7 @@ try {
   inputDevice.getDeviceList().then(data => {
     for (let i = 0; i < data.length; ++i) {
       inputDevice.getKeyboardType(data[i]).then(type => {
-        if (type == inputDevice.KeyboardType.ALPHABETIC_KEYBOARD) {
+        if (type === inputDevice.KeyboardType.ALPHABETIC_KEYBOARD) {
           // 物理键盘已连接
           isPhysicalKeyboardExist = true;
         }
@@ -53,7 +53,7 @@ try {
     console.log(`Device event info: ${JSON.stringify(data)}`);
     inputDevice.getKeyboardType(data.deviceId, (error, type) => {
       console.log("The keyboard type is: " + type);
-      if (type == inputDevice.KeyboardType.ALPHABETIC_KEYBOARD && data.type == 'add') {
+      if (type === inputDevice.KeyboardType.ALPHABETIC_KEYBOARD && data.type == 'add') {
         // 物理键盘已插入
         isPhysicalKeyboardExist = true;
       } else if (type == inputDevice.KeyboardType.ALPHABETIC_KEYBOARD && data.type == 'remove') {