如何限制Tkinter Entry组件的用户输入为1-16的整数？

我正在编写生成锦标赛对阵图的代码，其中包含让用户输入参赛队伍数量的功能。我希望限制输入内容仅为整数，且数值需大于1且小于等于16，请问如何修改以下Tkinter代码实现该需求？

原代码：

#Designing window for selecting number of teams for round-robin tournament(max 16)

from tkinter import *

def enter_numberofitems2():
  enter_numberofitems2_screen = Tk()
  enter_numberofitems2_screen.geometry("1000x500")
  enter_numberofitems2_screen.title("Enter Number of Players/Teams")
  Var1 = IntVar() 
  Label(enter_numberofitems2_screen, text= "Choose Number of Players/Teams", bg="yellow", 
  width="300", height="5", font=("Calibri", 20)).pack()
  Label(enter_numberofitems2_screen, text="").pack()
  Label(enter_numberofitems2_screen, text="Enter here", fg="green", height = "1", width = 
  "15", font=("calibri", 15)).pack()
  enter_teams = Entry(enter_numberofitems2_screen,textvariable=Var1).pack()
  Label(enter_numberofitems2_screen, text="").pack()
  Button(enter_numberofitems2_screen, text="Submit", height="5", width = "30", 
  bg="green").pack()

  enter_numberofitems2_screen.mainloop()

要实现输入限制，需要添加输入内容验证和数值范围检查，同时给用户提供清晰的错误反馈。以下是修改后的完整代码：

from tkinter import *
from tkinter import messagebox

def enter_numberofitems2():
    enter_numberofitems2_screen = Tk()
    enter_numberofitems2_screen.geometry("1000x500")
    enter_numberofitems2_screen.title("Enter Number of Players/Teams")
    Var1 = StringVar()  # 改用StringVar，避免IntVar自动转换空值为0的问题
    
    # 验证输入：仅允许输入数字
    def validate_input(new_value):
        return new_value == "" or new_value.isdigit()
    
    # 注册验证规则到窗口
    validate_cmd = enter_numberofitems2_screen.register(validate_input)
    
    Label(enter_numberofitems2_screen, text="Choose Number of Players/Teams", bg="yellow", 
          width="300", height="5", font=("Calibri", 20)).pack()
    Label(enter_numberofitems2_screen, text="").pack()
    Label(enter_numberofitems2_screen, text="Enter here", fg="green", height="1", width=15, 
          font=("calibri", 15)).pack()
    
    # 创建带实时验证的输入框
    enter_teams = Entry(enter_numberofitems2_screen, textvariable=Var1, 
                        validate="key", validatecommand=(validate_cmd, "%P"))
    enter_teams.pack()
    
    Label(enter_numberofitems2_screen, text="").pack()
    
    # 提交按钮的逻辑处理
    def submit():
        input_text = Var1.get()
        if not input_text:
            messagebox.showerror("错误", "请输入参赛队伍数量")
            return
        
        try:
            team_count = int(input_text)
            if 2 <= team_count <= 16:
                messagebox.showinfo("确认", f"参赛队伍数量已设置为：{team_count}")
                # 这里可以添加生成对阵图的后续逻辑
                enter_numberofitems2_screen.destroy()
            else:
                messagebox.showerror("错误", "请输入2到16之间的整数")
        except ValueError:
            messagebox.showerror("错误", "请输入有效的整数")
    
    Button(enter_numberofitems2_screen, text="Submit", height="5", width="30", 
           bg="green", command=submit).pack()

    enter_numberofitems2_screen.mainloop()

# 调用函数启动窗口
enter_numberofitems2()

关键修改点说明： #

• 输入内容验证：通过validate="key"和validate_input函数，实时限制输入框只能输入数字，避免非整数内容输入
• 数值范围检查：在提交逻辑中，将输入转为整数后检查是否在2-16区间内，不符合则弹出错误提示
• 变量类型调整：将IntVar改为StringVar，因为IntVar会把空输入自动转为0，干扰空值判断和验证逻辑
• 错误反馈：使用messagebox给用户明确的提示，告知输入错误的具体原因

内容的提问来源于stack exchange，提问作者MicrowaveBurrito