Merge pull request #250 from dynamsoft-docs/preview

update to internal commit 72e7a9f3

Author: Ellie-dynamsoft

api/interface/idocument/index.md

@@ -240,13 +240,13 @@ A Promise object which will be resolved with a boolean value.
 **Code Snippet**
 
 ```typescript
-const updateFirstPage = {
-    fileIndex: 1, // using the second page of new file.
+const updatePageOptions = {
+    fileIndex: 1, // Using the second page of the new multi-page file, such as PDF or TIFF.
 };
 
 const fileData = /*sample blob*/,
 
-await firstDoc.updatePage(firstDoc.pages[0], fileData, updateFirstPage);
+await firstDoc.updatePage(firstDoc.pages[0], fileData, updatePageOptions);
 ```
 
 **Promise Exception**

api/interface/idocument/updatepageoptions.md

@@ -27,7 +27,7 @@ interface UpdatePageOptions {
 
 ### fileIndex
 
-Specify the page index of the file. 
+Specify the page index of the multi-page file, such as a PDF or TIFF. 
 
 If it is not specified, the first page in the file will be the updated page.