diff --git a/frontend/Web/admin.html b/frontend/Web/admin.html
index f4aa041..22c599c 100644
--- a/frontend/Web/admin.html
+++ b/frontend/Web/admin.html
@@ -79,43 +79,8 @@
 
   <script src="/socket.io/socket.io.js"></script>
   <script src="/communication.js"></script>
+  <script src="/basic.js"></script>
   <script>
-    function showDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'block';
-    }
-
-    function hideDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'none';
-    }
-    function ChangeUsername(newUsername) {
-      document.getElementById('username').textContent = newUsername;
-    }
-    async function UpdateUserInfo(){
-      let nm=await GetMyName();
-      let pri=await GetMyPrivilege();
-      if(nm=='')
-      {
-        await RefreshSession();
-        nm=await GetMyName();
-        pri=await GetMyPrivilege();
-      }
-      if(pri==0)
-      {
-        ChangeUsername("[Guest]");
-      }
-      else if(pri==1)
-      {
-        ChangeUsername(nm);
-      }
-      else if(pri==3)
-      {
-        ChangeUsername(nm+" [Worker]");
-      }
-      else if(pri==7)
-      {
-        ChangeUsername(nm+" [Admin]");
-      }
-    }
     document.addEventListener('SessionReady', async () => {
       await UpdateUserInfo();
       if((await GetMyPrivilege())<3)
diff --git a/frontend/Web/basic.js b/frontend/Web/basic.js
new file mode 100644
index 0000000..6fa5ab3
--- /dev/null
+++ b/frontend/Web/basic.js
@@ -0,0 +1,36 @@
+function showDropdown() {
+  document.querySelector('.dropdown-content').style.display = 'block';
+}
+
+function hideDropdown() {
+  document.querySelector('.dropdown-content').style.display = 'none';
+}
+function ChangeUsername(newUsername) {
+  document.getElementById('username').textContent = newUsername;
+}
+async function UpdateUserInfo(){
+  let nm=await GetMyName();
+  let pri=await GetMyPrivilege();
+  if(nm=='')
+  {
+    await RefreshSession();
+    nm=await GetMyName();
+    pri=await GetMyPrivilege();
+  }
+  if(pri==0)
+  {
+    ChangeUsername("[Guest]");
+  }
+  else if(pri==1)
+  {
+    ChangeUsername(nm);
+  }
+  else if(pri==3)
+  {
+    ChangeUsername(nm+" [Worker]");
+  }
+  else if(pri==7)
+  {
+    ChangeUsername(nm+" [Admin]");
+  }
+}
\ No newline at end of file
diff --git a/frontend/Web/index.html b/frontend/Web/index.html
index fc9430e..f47efd5 100644
--- a/frontend/Web/index.html
+++ b/frontend/Web/index.html
@@ -40,43 +40,8 @@
 
   <script src="/socket.io/socket.io.js"></script>
   <script src="/communication.js"></script>
+  <script src="/basic.js"></script>
   <script>
-    function showDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'block';
-    }
-
-    function hideDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'none';
-    }
-    function ChangeUsername(newUsername) {
-      document.getElementById('username').textContent = newUsername;
-    }
-    async function UpdateUserInfo(){
-      let nm=await GetMyName();
-      let pri=await GetMyPrivilege();
-      if(nm=='')
-      {
-        await RefreshSession();
-        nm=await GetMyName();
-        pri=await GetMyPrivilege();
-      }
-      if(pri==0)
-      {
-        ChangeUsername("[Guest]");
-      }
-      else if(pri==1)
-      {
-        ChangeUsername(nm);
-      }
-      else if(pri==3)
-      {
-        ChangeUsername(nm+" [Worker]");
-      }
-      else if(pri==7)
-      {
-        ChangeUsername(nm+" [Admin]");
-      }
-    }
     document.addEventListener('SessionReady', async () => {
       console.log("receive event session ready");
       await UpdateUserInfo();
diff --git a/frontend/Web/index.js b/frontend/Web/index.js
index b0d92a9..1a97777 100644
--- a/frontend/Web/index.js
+++ b/frontend/Web/index.js
@@ -109,6 +109,9 @@ app.get('/communication.js', (req, res) => {
 app.get('/sessioninit.js', (req, res) => {
   res.sendFile(join(__dirname, 'sessioninit.js'));
 });
+app.get('/basic.js', (req, res) => {
+  res.sendFile(join(__dirname, 'basic.js'));
+});
 
 app.get('/basic.css', (req, res) => {
   res.sendFile(join(__dirname, 'basic.css'));
diff --git a/frontend/Web/login.html b/frontend/Web/login.html
index 47d9dda..5f6b18b 100644
--- a/frontend/Web/login.html
+++ b/frontend/Web/login.html
@@ -84,43 +84,8 @@
 
   <script src="/socket.io/socket.io.js"></script>
   <script src="/communication.js"></script>
+  <script src="/basic.js"></script>
   <script>
-    function showDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'block';
-    }
-
-    function hideDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'none';
-    }
-    function ChangeUsername(newUsername) {
-      document.getElementById('username').textContent = newUsername;
-    }
-    async function UpdateUserInfo(){
-      let nm=await GetMyName();
-      let pri=await GetMyPrivilege();
-      if(nm=='')
-      {
-        await RefreshSession();
-        nm=await GetMyName();
-        pri=await GetMyPrivilege();
-      }
-      if(pri==0)
-      {
-        ChangeUsername("[Guest]");
-      }
-      else if(pri==1)
-      {
-        ChangeUsername(nm);
-      }
-      else if(pri==3)
-      {
-        ChangeUsername(nm+" [Worker]");
-      }
-      else if(pri==7)
-      {
-        ChangeUsername(nm+" [Admin]");
-      }
-    }
     document.addEventListener('SessionReady', async () => {
       await UpdateUserInfo();
     });
diff --git a/frontend/Web/passwd.html b/frontend/Web/passwd.html
index cfb7085..b21608c 100644
--- a/frontend/Web/passwd.html
+++ b/frontend/Web/passwd.html
@@ -86,43 +86,8 @@
 
   <script src="/socket.io/socket.io.js"></script>
   <script src="/communication.js"></script>
+  <script src="/basic.js"></script>
   <script>
-    function showDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'block';
-    }
-
-    function hideDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'none';
-    }
-    function ChangeUsername(newUsername) {
-      document.getElementById('username').textContent = newUsername;
-    }
-    async function UpdateUserInfo(){
-      let nm=await GetMyName();
-      let pri=await GetMyPrivilege();
-      if(nm=='')
-      {
-        await RefreshSession();
-        nm=await GetMyName();
-        pri=await GetMyPrivilege();
-      }
-      if(pri==0)
-      {
-        ChangeUsername("[Guest]");
-      }
-      else if(pri==1)
-      {
-        ChangeUsername(nm);
-      }
-      else if(pri==3)
-      {
-        ChangeUsername(nm+" [Worker]");
-      }
-      else if(pri==7)
-      {
-        ChangeUsername(nm+" [Admin]");
-      }
-    }
     document.addEventListener('SessionReady', async () => {
       await UpdateUserInfo();
       if((await GetMyPrivilege())<1)
diff --git a/frontend/Web/register.html b/frontend/Web/register.html
index eb7e52c..f088bb7 100644
--- a/frontend/Web/register.html
+++ b/frontend/Web/register.html
@@ -86,43 +86,8 @@
 
   <script src="/socket.io/socket.io.js"></script>
   <script src="/communication.js"></script>
+  <script src="/basic.js"></script>
   <script>
-    function showDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'block';
-    }
-
-    function hideDropdown() {
-      document.querySelector('.dropdown-content').style.display = 'none';
-    }
-    function ChangeUsername(newUsername) {
-      document.getElementById('username').textContent = newUsername;
-    }
-    async function UpdateUserInfo(){
-      let nm=await GetMyName();
-      let pri=await GetMyPrivilege();
-      if(nm=='')
-      {
-        await RefreshSession();
-        nm=await GetMyName();
-        pri=await GetMyPrivilege();
-      }
-      if(pri==0)
-      {
-        ChangeUsername("[Guest]");
-      }
-      else if(pri==1)
-      {
-        ChangeUsername(nm);
-      }
-      else if(pri==3)
-      {
-        ChangeUsername(nm+" [Worker]");
-      }
-      else if(pri==7)
-      {
-        ChangeUsername(nm+" [Admin]");
-      }
-    }
     document.addEventListener('SessionReady', async () => {
       await UpdateUserInfo();
     });