diff --git a/zh-cn/application-dev/reference/apis/js-apis-file-hash.md b/zh-cn/application-dev/reference/apis/js-apis-file-hash.md
index a38e3189c58e52af35f5dae9a9ab3a7d136c1a7a..911dac45c0fa4c0496587f491cf8f653872ac760 100644
--- a/zh-cn/application-dev/reference/apis/js-apis-file-hash.md
+++ b/zh-cn/application-dev/reference/apis/js-apis-file-hash.md
@@ -92,6 +92,7 @@ hash(path: string, algorithm: string, callback: AsyncCallback<string>): vo
 
 **示例：**
   ```js
+  let filePath = pathDir + "/test.txt";
   Hash.hash(filePath, "sha256", (err, str) => {
     if (err) {
       console.info("calculate file hash failed with error message: " + err.message + ", error code: " + err.code);