Python tkinter Label控件无法完整输出全部打印结果如何解决

问题根因 #

你在遍历对比的循环中，每次都直接给result_label的text属性赋新值，新内容会直接覆盖之前的旧内容，所以最终界面上只保留了最后一条对比结果；而控制台执行print(x)是每次新增一行输出，因此能完整展示所有结果。同时你当前代码还存在两个小问题：缺失sys模块导入（用到了sys.stderr但没有对应导入语句）、用了内置函数名cmp做自定义变量、存在无意义的重复定义DIRS/FILES和空循环代码。

修复方案 #

推荐使用Text控件替代原来的Label来展示多行结果，更适合多行文本的滚动展示，修改后的完整代码如下：

import filecmp
import os
import sys
import tkinter as tk
import tkinter.font as tkFont

def gg():
    # 先清空之前的输出内容
    result_text.delete(1.0, tk.END)
    disk = number_entry.get()

    if disk == "2" :
        DIRS = [r'C:\Newtest\1', r'C:\Newtest\2', r'C:\Newtest\3',r'C:\Newtest\4',r'C:\Newtest\5',r'C:\Newtest\6',r'C:\Newtest\7',r'C:\Newtest\8',r'C:\Newtest\9',r'C:\Newtest\10']
        FILES = [('copy1.txt', 'copy2.txt'), ('fcmp1.txt', 'fcmp2.txt'), ('filecp1.txt', 'filecp2.txt')]

        for e, dir in enumerate(DIRS, 1):
            cmp_res = True
            for file in FILES:
                try:
                    if not filecmp.cmp(os.path.join(dir, file[0]), os.path.join(dir, file[1])):
                        cmp_res = False
                        break
                except Exception as ex:
                        err_info = f'Error -> {ex}\n'
                        print(err_info, file=sys.stderr)
                        result_text.insert(tk.END, err_info)
                        continue
            x = f'E_{e} compare {"pass" if cmp_res else "fail"}\n'
            print(x)
            # 把新结果追加到Text控件末尾
            result_text.insert(tk.END, x)

window = tk.Tk()
window.title('XXX')
window.geometry('1200x700')
window.configure(background='Azure')

fontExample = tkFont.Font(family="Segoe UI", size=20)
fontExample2 = tkFont.Font(family="Segoe UI", size=10)
fontExample3 = tkFont.Font(family="Segoe UI", size=15)
header_label = tk.Label(window, text='XXXX',font=fontExample)
header_label.pack()

number_frame = tk.Frame(window)
number_frame.pack(side=tk.TOP, pady=10)
number_label = tk.Label(number_frame, text='Number of disks',font=fontExample2)
number_label.pack(side=tk.LEFT, padx=5)
number_entry = tk.Entry(number_frame)
number_entry.pack(side=tk.LEFT)
# 替换原来的Label为Text控件，支持滚动查看多行结果
result_text = tk.Text(window, font=fontExample3, width=80, height=20, bg='white', wrap=tk.WORD)
result_text.pack(pady=10)
calculate_btn = tk.Button(window, text='First calculate', command=gg,font=fontExample3)
calculate_btn.pack(pady=5)

window.mainloop()

如果你坚持用Label控件实现 #

只需要修改gg函数内的赋值逻辑，每次把新结果拼到原有内容后即可：

def gg():
    # 先清空之前的结果
    result_label.configure(text="")
    disk = number_entry.get()

    if disk == "2" :
        DIRS = [r'C:\Newtest\1', r'C:\Newtest\2', r'C:\Newtest\3',r'C:\Newtest\4',r'C:\Newtest\5',r'C:\Newtest\6',r'C:\Newtest\7',r'C:\Newtest\8',r'C:\Newtest\9',r'C:\Newtest\10']
        FILES = [('copy1.txt', 'copy2.txt'), ('fcmp1.txt', 'fcmp2.txt'), ('filecp1.txt', 'filecp2.txt')]

        for e, dir in enumerate(DIRS, 1):
            cmp_res = True
            for file in FILES:
                try:
                    if not filecmp.cmp(os.path.join(dir, file[0]), os.path.join(dir, file[1])):
                        cmp_res = False
                        break
                except Exception as ex:
                        print(f'Error -> {ex}', file=sys.stderr)
                        continue
            x = (f'E_{e} compare {"pass" if cmp_res else "fail"}\n')
            print(x)
            # 拼接新内容到原有内容末尾
            old_text = result_label.cget("text")
            result_label.configure(text=old_text + x,wraplength=300,font=fontExample3)

内容的提问来源于stack exchange，提问作者Wu Ru