auto save

my_app.py

 import tkinter
 from tkinter import messagebox
 import json
-with open("user.txt","r",encoding="utf-8") as f:
+'''with open("user.txt","r",encoding="utf-8") as f:
     info=f.read()
-    users=json.loads(info)
+    users=json.loads(info)'''
 def login_to_reg():    # 登录界面转注册界面
     app_login.root.destroy()
     global app_reg
@@ -11,13 +11,38 @@ def login_to_reg():    # 登录界面转注册界面
     app_login.show()
 
 def reg_to_login():   # 注册界面转登录界面
-    pass
+    app_reg.root.destroy()
+    global app_login
+    app_reg=My_login()
+    app_reg.show()
 
 def register():     # 注册验证
-    pass
+    if name=="" or password1=="" or password2=="":
+        messagebox.showwarning("警告","未填写完整注册资料")
+    elif name in users:
+        messagebox.showwarning("提示","用户名已经存在!")
+    elif password1!=password2:
+        messagebox.showwarning("错误","确认密码填写错误!")
+    else:
+        users[name]=password1
+        content=json.dumps(users)
+        '''with open("user.txt","r",encoding="utf-8") as f:
+            file.write(content)'''
+        messagebox.showwarning("成功","注册成功")
         
 def login():    # 登录验证
-    pass    
+    if name=="" or password=="":
+        messagebox.showwarning("警告","未填写信息")
+    elif name in users:
+        messagebox.showwarning("提示","用户名已经存在!")
+    elif password1!=password2:
+        messagebox.showwarning("错误","确认密码填写错误!")
+    else:
+        users[name]=password1
+        content=json.dumps(users)
+        with open("user.txt","r",encoding="utf-8") as f:
+            file.write(content)
+        messagebox.showwarning("成功","注册成功")   
 
 class My_login():       # 登录窗口
     def __init__(self):