方法一:使用keys()方法 keys()方法可以返回字典中所有的键,我们可以将其转换为列表,然后根据需求进行筛选。下面是一个示例代码: student={'name':'Tom','age':18,'gender':'male','class':'Grade 1'}# 输出所有键all_keys=list(student.keys())print(all_keys)# 输出 [
Python 字典(Dictionary)字典是另一种可变容器模型,且可存储任意类型对象。字典的每个键值 key:value 对用冒号 : 分割,每个键值对之间用逗号 , 分割,整个字典包括在花括号 {} 中,格式如下所示: d = {key1 : value1, key2 : value2 }注意:dict 作为Python 的关键字和内置函数,变量名不建议命名为 dict。
print(dictionaryKeys)# Output: dict_keys([1, 2, 3]) keys() Syntax The syntax of thekeys()method is: dict.keys() Here,dictis a dictionary whose keys are extracted. keys() Parameters Thekeys()method doesn't take any parameters. keys() Return Value Thekeys()method returns: a view obj...
我们可以使用for循环来遍历键值对,并使用print函数进行打印操作。 # 分行打印字典的键值对forkey,valueinitems:print(key,value) 1. 2. 3. 完整代码示例 # 创建一个字典my_dict={}# 获取字典的键值对items=my_dict.items()# 分行打印字典的键值对forkey,valueinitems:print(key,value) 1. 2. 3. 4. 5...
First we create a dictionary 'dict' which contains keys: 'Name' and 'Age'. Then we retrieve all the keys of the dictionary using keys() method.Open Compiler # creating the dictionary dict = {'Name': 'Zara', 'Age': 7} # Printing the result print ("Value : %s" % dict.keys()) ...
1stus={'addr':'beijing','sex':'nan','phone':'2346465','name':'海龙','email':'13e@aa.com'}2print(stus.keys())#取出所有key3print(stus.values())#取出所有value4stus.update({'money':10000})#更新字典值,如果key存在的话,就更新,不存在的话就添加5print(stus.items())#将字典转成list...
python print("yuan" in "hello yuan") print(100 in [1, 10, 100, 1000]) print("yuan" not in ["rain","eric","alvin","hello yuan"])【6】运算符优先级在Python中,运算符优先级指定了在表达式中运算符的执行顺序。以下是Python中常见运算符的优先级从高到低的顺序(同一优先级的运算符从左到右...
importnumpyasnpdeftest(a):a[0]=np.nanm=[1,2,3]test(m)print(m) output: [nan, 2, 3] Note python has this really weird error if you define local variable in a function same name as the global variable, program will promptUnboundLocalError. ...
for key,value in zip(my_keys, my_values): my_dictionary[key] = value print(my_dictionary)Copy Thezipfunction matches elements from two lists by index, creating key-value pairs. Conclusion This guide showed how to add items to a Python dictionary. All methods provide unique functionalities, ...
keys() method, then does: for k, v in E: D[k] = v In either case, this is followed by: for k in F: D[k] = F[k] 注释(8)(9)(10)的三个操作,正好对应帮助文档中所说的三种情况: 注释(8)中的参数是字典,字典有 keys() 方法; 注释(9)中的参数是列表(列表的成员是元组),且可...