diff --git a/AppDataSecurity/entry/src/main/ets/pages/Index.ets b/AppDataSecurity/entry/src/main/ets/pages/Index.ets
index 77abcf988a9f5d14c18ffe1e8a8afae3b860c9c2..2baf55383cc4e367ea0f6de1dd430508bdbce339 100644
--- a/AppDataSecurity/entry/src/main/ets/pages/Index.ets
+++ b/AppDataSecurity/entry/src/main/ets/pages/Index.ets
@@ -65,7 +65,7 @@ struct Index {
   }
 
   // [Start get_el2_path]
-  getEl2Path() {
+  getEl2Path(): void {
     let context = this.getUIContext().getHostContext() as common.UIAbilityContext;
     context.area = contextConstant.AreaMode.EL2;
     let filePath = context.filesDir + '/health_data.txt';
@@ -74,7 +74,7 @@ struct Index {
   // [End get_el2_path]
 
   // [Start get_el1_path]
-  getEl1Path() {
+  getEl1Path(): void {
     let context = this.getUIContext().getHostContext() as common.UIAbilityContext;
     context.area = contextConstant.AreaMode.EL1;
     let filePath = context.filesDir + '/health_data.txt';
@@ -83,14 +83,14 @@ struct Index {
   // [End get_el1_path]
 }
 
-let aesKeyAlias = 'test_aesKeyAlias';
+let aesKeyAlias: string = 'test_aesKeyAlias';
 let handle: number;
-let plainText = '123456';
-let IV = '001122334455';
+let plainText: string = '123456';
+let IV: string = '001122334455';
 let cipherData: Uint8Array;
 
 // [Start write_file]
-function writeFile(filePath: string, data: string) {
+function writeFile(filePath: string, data: string): void {
   try {
     let file = fileIo.openSync(filePath, fileIo.OpenMode.READ_WRITE | fileIo.OpenMode.CREATE);
     let writeLen = fileIo.writeSync(file.fd, data);
@@ -125,18 +125,18 @@ function readFile(filePath: string): string {
 }
 // [End write_file]
 
-function StringToUint8Array(str: string) {
+function StringToUint8Array(str: string): Uint8Array {
   let textEncoder = util.TextEncoder.create('utf-8');
   return textEncoder.encodeInto(str);
 }
 
-function Uint8ArrayToString(fileData: Uint8Array) {
+function Uint8ArrayToString(fileData: Uint8Array): string {
   let textDecoder = util.TextDecoder.create('utf-8');
   return textDecoder.decodeToString(fileData);
 }
 
 // [Start get_aes_generate_properties]
-function GetAesGenerateProperties() {
+function GetAesGenerateProperties(): Array<huks.HuksParam> {
   let properties: Array<huks.HuksParam> = [{
     tag: huks.HuksTag.HUKS_TAG_ALGORITHM,
     value: huks.HuksKeyAlg.HUKS_ALG_AES
@@ -153,7 +153,7 @@ function GetAesGenerateProperties() {
 // [End get_aes_generate_properties]
 
 // [Start get_aes_encrypt_properties]
-function GetAesEncryptProperties() {
+function GetAesEncryptProperties(): Array<huks.HuksParam> {
   let properties: Array<huks.HuksParam> = [{
     tag: huks.HuksTag.HUKS_TAG_ALGORITHM,
     value: huks.HuksKeyAlg.HUKS_ALG_AES
@@ -178,7 +178,7 @@ function GetAesEncryptProperties() {
 // [End get_aes_encrypt_properties]
 
 // [Start get_aes_decrypt_properties]
-function GetAesDecryptProperties() {
+function GetAesDecryptProperties(): Array<huks.HuksParam> {
   let properties: Array<huks.HuksParam> = [{
     tag: huks.HuksTag.HUKS_TAG_ALGORITHM,
     value: huks.HuksKeyAlg.HUKS_ALG_AES
@@ -203,7 +203,7 @@ function GetAesDecryptProperties() {
 // [End get_aes_decrypt_properties]
 
 // [Start generate_aes_key]
-async function GenerateAesKey() {
+async function GenerateAesKey(): Promise<void> {
   let genProperties = GetAesGenerateProperties();
   let options: huks.HuksOptions = {
     properties: genProperties
@@ -219,7 +219,7 @@ async function GenerateAesKey() {
 // [End generate_aes_key]
 
 // [Start encrypt_data]
-async function EncryptData() {
+async function EncryptData(): Promise<void> {
   let encryptProperties = GetAesEncryptProperties();
   let options: huks.HuksOptions = {
     properties: encryptProperties,
@@ -243,7 +243,7 @@ async function EncryptData() {
     })
 }
 
-async function DecryptData() {
+async function DecryptData(): Promise<void> {
   let decryptOptions = GetAesDecryptProperties()
   let options: huks.HuksOptions = {
     properties: decryptOptions,
@@ -267,7 +267,7 @@ async function DecryptData() {
 }
 // [End encrypt_data]
 
-async function DeleteKey() {
+async function DeleteKey(): Promise<void> {
   let emptyOptions: huks.HuksOptions = {
     properties: []
   };