有谁知道为什么我没有得到输出，代码编译但 returns 没有输出

Question

employees =[
    {
        "name": "John Doe",
        "job": "Software Engineer",
        "City": "Vancouver",
        "age": 34,
        "status": "single"
    },
    {
        "name": "Alicia Smith",
        "job": "Director",
        "City": "New York",
        "age": 38,
        "status": "Married"
    }
] 

keys = ["name", "age"]


if "name" and "age" in employees:
 newDict = employees.pop("name" and "age")
 print(newDict)

Answer 1

首先你在代码中遇到了两个错误，第一个是因为 if 语句不正确，这就是为什么没有被执行的原因。其次，你不能在数组中弹出字典，你必须选择每个字典，然后弹出它们或将它们放入循环中，就像这个解决方案

employees =[ { "name": "John Doe", "job": "Software Engineer", "City": "Vancouver", "age": 34, "status": "single" }, { "name": "Alicia Smith", "job": "Director", "City": "New York", "age": 38, "status": "Married" } ]
newDict = []
for i in employees:
    if "name" and "age" in i:
        i.pop("name" and "age")
        newDict.append(i)
print(newDict)

Answer 2

您的代码中有一些错误。我相信您正试图从存在的字典中删除键 name 和 age。请尝试以下操作：

employees = [
    {
        "name": "John Doe",
        "job": "Software Engineer",
        "City": "Vancouver",
        "age": 34,
        "status": "single"
    },
    {
        "name": "Alicia Smith",
        "job": "Director",
        "City": "New York",
        "age": 38,
        "status": "Married"
    }
]

newDict = []
for d in employees:   # First iterate over the dictionaries
    if "name" in d:   # If the key "name" is there in the dictionary
        d.pop("name") # Remove it
    if "age" in d:    # Check if "age" is there in the keys
        d.pop("age")  # Remove it too if present
    newDict.append(d) # Add the updated dictionary to our list
print(newDict)

Answer 3

您可以使用 dict comprehension inside a list comprehension 作为单行。

print([{k: v for k, v in d.items() if k not in keys} for d in employees])

如果你想在多行中执行它，你应该在从字典中删除项目之前复制字典。否则，您将收到以下错误。

RuntimeError: dictionary changed size during iteration

有谁知道为什么我没有得到输出，代码编译但 returns 没有输出

Does anyone know why i do not get an output, the code does compile but returns no output

python

list

set