cs50 pset7包含语法

问题描述

我正在解决问题的roster.py部分，但出现错误：

   File "roster.py",line 17
    print(f"{row["first"]} {row["middle"]} {row["last"]},born {row["birth"]}")
                      ^
SyntaxError: invalid Syntax

我的代码：

import sys
from cs50 import sql

if len(sys.argv) != 2:
    print("Needs two command-line argument")
    exit(1)

db = sql("sqlite:///students.db")

house = sys.argv[1]

results = db.execute("SELECT * FROM students WHERE house = ?",house)


for row in results:
    if row["middle"] != None:
        print(f"{row["first"]} {row["middle"]} {row["last"]},born {row["birth"]}")
    else:
        print(f"{row["first"]} {row["last"]},born {row["birth"]}")

解决方法

您的报价有误。试试这个：

for row in results:
    if row["middle"] != None:
        print(f'{row["first"]} {row["middle"]} {row["last"]},born {row["birth"]}')
    else:
        print(f'{row["first"]} {row["last"]},born {row["birth"]}')

,

如果您尝试打印row [“ middle”]值，依此类推。

for row in results:
    if row["middle"] != None:
        print(f"{"+row["first"]+"} {"+row["middle"]+"} {"+row["last"]+"},born {"+row["birth"]+"}")
    else:
       print(f"{"+row["first"]+"} {"+row["last"]+"},born {"+row["birth"]+"}")