在组合框中查看连接在一起并用连字符分隔的数据库的内容

Question

如何在组合框中（在 City1 和 City2 字段中）显示同一行的内容并结合破折号形成旅行目的地？

例如，我想在组合框中显示：伦敦-曼彻斯特，然后是巴黎-波尔多（两个目的地，所以组合框中有两个项目）。

在代码中我尝试解决它，但是你可以看到它是错误的，非常错误，你已经可以肉眼看到它。我是 Python 新手

CREATE TABLE "destinations" (
    "id"    INTEGER,
    "city1" INTEGER, #London, #Paris
    "city2" INTEGER, #Manchester, #Bordeaux
    PRIMARY KEY("id" AUTOINCREMENT)
);

1, London, Manchester
2, Paris, Bordeaux

Tkinter 窗口：

from tkinter import *
from tkinter import ttk
import tkinter as tk
import sqlite3

app=Tk()
app.title(" ")
app.geometry("300x200")

con = sqlite3.connect('database.db')
cursor = con.cursor()

combo=ttk.Combobox(app, width=21)
combo.place(x=30, y=20)
combo.config(values=combo)
combo.bind('<<ComboboxSelected>>')
combo.set("Select")
combos=["destinations"]

city1= cursor.execute "SELECT city1 FROM destinations"
city2= cursor.execute "SELECT city1 FROM destinations"

destinations = "city1" "-" "city2"

app.mainloop()
 

Answer 1

您可以通过任一方式组合这两个字段

• 使用 SQLite concatenate operator ||

cursor.execute('SELECT city1 || "-" || city2 FROM destinations')
values = [row[0] for row in cursor]

• 或使用 Python 字符串 .join()

cursor.execute('SELECT city1, city2 FROM destinations')
values = ['-'.join(row) for row in cursor]

然后将结果赋值给Combobox的values选项：

combo.config(values=values)

---

完整示例代码：

import tkinter as tk
from tkinter import ttk
import sqlite3

app = tk.Tk()
app.geometry('300x200')

cnx = sqlite3.connect('database.db')
cursor = cnx.cursor()

cursor.execute('SELECT city1 || "-" || city2 FROM destinations')
values = [row[0] for row in cursor]
'''
cursor.execute('SELECT city1, city2 FROM destinations')
values = ['-'.join(row) for row in cursor]
'''
print(values)

combo = ttk.Combobox(app, width=21, values=values, state='readonly')
combo.place(x=30, y=20)

app.mainloop()