{"id":1064952,"date":"2024-12-31T16:13:22","date_gmt":"2024-12-31T08:13:22","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/1064952.html"},"modified":"2024-12-31T16:13:25","modified_gmt":"2024-12-31T08:13:25","slug":"python%e4%b8%ad%e5%a6%82%e4%bd%95%e7%9f%a5%e9%81%93key%e5%80%bc%e6%98%af%e5%a4%9a%e5%b0%91","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/1064952.html","title":{"rendered":"python\u4e2d\u5982\u4f55\u77e5\u9053key\u503c\u662f\u591a\u5c11"},"content":{"rendered":"

\"python\u4e2d\u5982\u4f55\u77e5\u9053key\u503c\u662f\u591a\u5c11\"<\/p>\n

\u5728Python\u4e2d\uff0c\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u51e0\u79cd\u65b9\u5f0f\u6765\u83b7\u53d6\u5b57\u5178\u7684\u952e\u503c\uff1a\u4f7f\u7528\u5b57\u5178\u7684keys()\u65b9\u6cd5\u3001\u4f7f\u7528for\u5faa\u73af\u904d\u5386\u5b57\u5178\u3001\u4f7f\u7528\u5b57\u5178\u7684items()\u65b9\u6cd5<\/strong>\u3002\u5176\u4e2d\uff0c\u4f7f\u7528\u5b57\u5178\u7684keys()\u65b9\u6cd5\u53ef\u4ee5\u76f4\u63a5\u83b7\u53d6\u6240\u6709\u952e\u503c\uff0c\u8fd9\u4e5f\u662f\u6700\u5e38\u7528\u7684\u65b9\u6cd5\u3002<\/p>\n<\/p>\n

\u4f7f\u7528\u5b57\u5178\u7684keys()\u65b9\u6cd5\u662f\u6700\u7b80\u5355\u76f4\u63a5\u7684\u4e00\u79cd\u65b9\u5f0f\u3002\u8be5\u65b9\u6cd5\u4f1a\u8fd4\u56de\u4e00\u4e2a\u5305\u542b\u6240\u6709\u952e\u7684\u89c6\u56fe\u5bf9\u8c61\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u5c06\u5176\u8f6c\u6362\u4e3a\u5217\u8868\u6765\u8f7b\u677e\u67e5\u770b\u6240\u6709\u7684\u952e\u503c\u3002\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u8be6\u7ec6\u4ecb\u7ecd\u8fd9\u4e9b\u65b9\u6cd5\u7684\u5177\u4f53\u5b9e\u73b0\u548c\u4f7f\u7528\u573a\u666f\u3002<\/p>\n<\/p>\n

\u4e00\u3001\u4f7f\u7528\u5b57\u5178\u7684keys()\u65b9\u6cd5<\/p>\n<\/p>\n

\u5b57\u5178\u7684keys()\u65b9\u6cd5\u4f1a\u8fd4\u56de\u4e00\u4e2a\u5305\u542b\u5b57\u5178\u4e2d\u6240\u6709\u952e\u7684\u89c6\u56fe\u5bf9\u8c61\u3002\u8fd9\u4e2a\u89c6\u56fe\u5bf9\u8c61\u662f\u52a8\u6001\u7684\uff0c\u610f\u5473\u7740\u5982\u679c\u5b57\u5178\u6539\u53d8\u4e86\uff0c\u89c6\u56fe\u5bf9\u8c61\u4e5f\u4f1a\u6539\u53d8\u3002\u6211\u4eec\u53ef\u4ee5\u5c06\u8fd9\u4e2a\u89c6\u56fe\u5bf9\u8c61\u8f6c\u6362\u4e3a\u5217\u8868\uff0c\u4ee5\u4fbf\u66f4\u76f4\u89c2\u5730\u67e5\u770b\u6240\u6709\u7684\u952e\u503c\u3002<\/p>\n<\/p>\n

my_dict = {'name': 'Alice', 'age': 25, 'city': 'New York'}<\/p>\n
keys = my_dict.keys()<\/p>\n
print(list(keys))  # \u8f93\u51fa: ['name', 'age', 'city']<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u975e\u5e38\u7b80\u6d01\u660e\u4e86\uff0c\u9002\u7528\u4e8e\u9700\u8981\u5feb\u901f\u83b7\u53d6\u6240\u6709\u952e\u503c\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u4e8c\u3001\u4f7f\u7528for\u5faa\u73af\u904d\u5386\u5b57\u5178<\/p>\n<\/p>\n
\u53e6\u4e00\u79cd\u83b7\u53d6\u5b57\u5178\u952e\u503c\u7684\u65b9\u6cd5\u662f\u4f7f\u7528for\u5faa\u73af\u904d\u5386\u5b57\u5178\u3002\u5728\u904d\u5386\u8fc7\u7a0b\u4e2d\uff0c\u6bcf\u6b21\u8fed\u4ee3\u90fd\u4f1a\u8fd4\u56de\u4e00\u4e2a\u952e\u503c\u5bf9\u4e2d\u7684\u952e\u3002<\/p>\n<\/p>\n
my_dict = {'name': 'Alice', 'age': 25, 'city': 'New York'}<\/p>\n
for key in my_dict:<\/p>\n
    print(key)  # \u5206\u522b\u8f93\u51fa: name, age, city<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u5bf9\u952e\u503c\u8fdb\u884c\u8fdb\u4e00\u6b65\u5904\u7406\u7684\u60c5\u51b5\uff0c\u4f8b\u5982\u5728\u904d\u5386\u8fc7\u7a0b\u4e2d\u5bf9\u952e\u503c\u8fdb\u884c\u67d0\u4e9b\u64cd\u4f5c\u3002<\/p>\n<\/p>\n
\u4e09\u3001\u4f7f\u7528\u5b57\u5178\u7684items()\u65b9\u6cd5<\/p>\n<\/p>\n
\u5b57\u5178\u7684items()\u65b9\u6cd5\u4f1a\u8fd4\u56de\u4e00\u4e2a\u5305\u542b\u6240\u6709\u952e\u503c\u5bf9\u7684\u89c6\u56fe\u5bf9\u8c61\u3002\u901a\u8fc7\u904d\u5386\u8fd9\u4e2a\u89c6\u56fe\u5bf9\u8c61\uff0c\u6211\u4eec\u53ef\u4ee5\u540c\u65f6\u83b7\u53d6\u952e\u548c\u503c\u3002<\/p>\n<\/p>\n
my_dict = {'name': 'Alice', 'age': 25, 'city': 'New York'}<\/p>\n
for key, value in my_dict.items():<\/p>\n
    print(f'Key: {key}, Value: {value}')  # \u5206\u522b\u8f93\u51fa: Key: name, Value: Alice \u7b49<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u540c\u65f6\u5904\u7406\u952e\u548c\u503c\u7684\u60c5\u51b5\uff0c\u4f8b\u5982\u6253\u5370\u6240\u6709\u952e\u503c\u5bf9\u6216\u6839\u636e\u952e\u503c\u5bf9\u8fdb\u884c\u67d0\u4e9b\u64cd\u4f5c\u3002<\/p>\n<\/p>\n
\u56db\u3001\u4f7f\u7528\u5b57\u5178\u7684get()\u65b9\u6cd5<\/p>\n<\/p>\n
\u5b57\u5178\u7684get()\u65b9\u6cd5\u53ef\u4ee5\u6839\u636e\u63d0\u4f9b\u7684\u952e\u83b7\u53d6\u5bf9\u5e94\u7684\u503c\u3002\u5982\u679c\u952e\u4e0d\u5b58\u5728\uff0c\u5219\u8fd4\u56deNone\u6216\u6307\u5b9a\u7684\u9ed8\u8ba4\u503c\u3002\u867d\u7136\u8fd9\u4e0d\u662f\u76f4\u63a5\u83b7\u53d6\u952e\u503c\u7684\u65b9\u6cd5\uff0c\u4f46\u5728\u67d0\u4e9b\u573a\u666f\u4e0b\u975e\u5e38\u6709\u7528\uff0c\u4f8b\u5982\u5728\u5904\u7406\u7528\u6237\u8f93\u5165\u65f6\u68c0\u67e5\u952e\u662f\u5426\u5b58\u5728\u3002<\/p>\n<\/p>\n
my_dict = {'name': 'Alice', 'age': 25, 'city': 'New York'}<\/p>\n
key_to_check = 'age'<\/p>\n
value = my_dict.get(key_to_check, 'Key not found')<\/p>\n
print(value)  # \u8f93\u51fa: 25<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u6839\u636e\u952e\u83b7\u53d6\u503c\u5e76\u8fdb\u884c\u8fdb\u4e00\u6b65\u5904\u7406\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u4e94\u3001\u4f7f\u7528\u5b57\u5178\u7684setdefault()\u65b9\u6cd5<\/p>\n<\/p>\n
\u5b57\u5178\u7684setdefault()\u65b9\u6cd5\u53ef\u4ee5\u83b7\u53d6\u6307\u5b9a\u952e\u7684\u503c\uff0c\u5982\u679c\u952e\u4e0d\u5b58\u5728\uff0c\u5219\u5c06\u952e\u6dfb\u52a0\u5230\u5b57\u5178\u4e2d\uff0c\u5e76\u5c06\u5176\u503c\u8bbe\u7f6e\u4e3a\u63d0\u4f9b\u7684\u9ed8\u8ba4\u503c\u3002\u8fd9\u4e2a\u65b9\u6cd5\u7c7b\u4f3c\u4e8eget()\u65b9\u6cd5\uff0c\u4f46\u4f1a\u5728\u952e\u4e0d\u5b58\u5728\u65f6\u4fee\u6539\u5b57\u5178\u3002<\/p>\n<\/p>\n
my_dict = {'name': 'Alice', 'age': 25, 'city': 'New York'}<\/p>\n
key_to_check = 'country'<\/p>\n
value = my_dict.setdefault(key_to_check, 'USA')<\/p>\n
print(value)  # \u8f93\u51fa: USA<\/p>\n
print(my_dict)  # \u8f93\u51fa: {'name': 'Alice', 'age': 25, 'city': 'New York', 'country': 'USA'}<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u786e\u4fdd\u5b57\u5178\u4e2d\u5b58\u5728\u7279\u5b9a\u952e\u7684\u60c5\u51b5\uff0c\u540c\u65f6\u5728\u952e\u4e0d\u5b58\u5728\u65f6\u8bbe\u7f6e\u9ed8\u8ba4\u503c\u3002<\/p>\n<\/p>\n
\u516d\u3001\u4f7f\u7528\u5b57\u5178\u7684pop()\u65b9\u6cd5<\/p>\n<\/p>\n
\u5b57\u5178\u7684pop()\u65b9\u6cd5\u53ef\u4ee5\u6839\u636e\u63d0\u4f9b\u7684\u952e\u5220\u9664\u952e\u503c\u5bf9\uff0c\u5e76\u8fd4\u56de\u5bf9\u5e94\u7684\u503c\u3002\u5982\u679c\u952e\u4e0d\u5b58\u5728\uff0c\u5219\u8fd4\u56de\u6307\u5b9a\u7684\u9ed8\u8ba4\u503c\u6216\u5f15\u53d1KeyError\u5f02\u5e38\u3002\u867d\u7136\u8fd9\u4e0d\u662f\u76f4\u63a5\u83b7\u53d6\u952e\u503c\u7684\u65b9\u6cd5\uff0c\u4f46\u5728\u67d0\u4e9b\u573a\u666f\u4e0b\u975e\u5e38\u6709\u7528\uff0c\u4f8b\u5982\u5728\u5904\u7406\u5b57\u5178\u65f6\u9700\u8981\u540c\u65f6\u83b7\u53d6\u5e76\u5220\u9664\u67d0\u4e2a\u952e\u503c\u5bf9\u3002<\/p>\n<\/p>\n
my_dict = {'name': 'Alice', 'age': 25, 'city': 'New York'}<\/p>\n
key_to_remove = 'city'<\/p>\n
value = my_dict.pop(key_to_remove, 'Key not found')<\/p>\n
print(value)  # \u8f93\u51fa: New York<\/p>\n
print(my_dict)  # \u8f93\u51fa: {'name': 'Alice', 'age': 25}<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u5728\u83b7\u53d6\u952e\u503c\u5bf9\u7684\u540c\u65f6\u4ece\u5b57\u5178\u4e2d\u5220\u9664\u8be5\u952e\u503c\u5bf9\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u4e03\u3001\u4f7f\u7528\u5b57\u5178\u7684fromkeys()\u65b9\u6cd5<\/p>\n<\/p>\n
\u5b57\u5178\u7684fromkeys()\u65b9\u6cd5\u53ef\u4ee5\u6839\u636e\u63d0\u4f9b\u7684\u952e\u5e8f\u5217\u521b\u5efa\u4e00\u4e2a\u65b0\u7684\u5b57\u5178\uff0c\u5e76\u5c06\u6240\u6709\u952e\u7684\u503c\u8bbe\u7f6e\u4e3a\u63d0\u4f9b\u7684\u9ed8\u8ba4\u503c\u3002\u867d\u7136\u8fd9\u4e0d\u662f\u76f4\u63a5\u83b7\u53d6\u952e\u503c\u7684\u65b9\u6cd5\uff0c\u4f46\u5728\u67d0\u4e9b\u573a\u666f\u4e0b\u975e\u5e38\u6709\u7528\uff0c\u4f8b\u5982\u9700\u8981\u6839\u636e\u4e00\u7ec4\u952e\u521b\u5efa\u4e00\u4e2a\u65b0\u7684\u5b57\u5178\u3002<\/p>\n<\/p>\n
keys = ['name', 'age', 'city']<\/p>\n
default_value = 'Unknown'<\/p>\n
new_dict = dict.fromkeys(keys, default_value)<\/p>\n
print(new_dict)  # \u8f93\u51fa: {'name': 'Unknown', 'age': 'Unknown', 'city': 'Unknown'}<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u5feb\u901f\u521b\u5efa\u4e00\u4e2a\u5305\u542b\u7279\u5b9a\u952e\u7684\u5b57\u5178\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u516b\u3001\u4f7f\u7528\u5b57\u5178\u7684update()\u65b9\u6cd5<\/p>\n<\/p>\n
\u5b57\u5178\u7684update()\u65b9\u6cd5\u53ef\u4ee5\u5c06\u53e6\u4e00\u4e2a\u5b57\u5178\u6216\u952e\u503c\u5bf9\u5e8f\u5217\u4e2d\u7684\u952e\u503c\u5bf9\u6dfb\u52a0\u5230\u5f53\u524d\u5b57\u5178\u4e2d\u3002\u5982\u679c\u5b58\u5728\u76f8\u540c\u7684\u952e\uff0c\u5219\u4f1a\u66f4\u65b0\u5176\u503c\u3002\u867d\u7136\u8fd9\u4e0d\u662f\u76f4\u63a5\u83b7\u53d6\u952e\u503c\u7684\u65b9\u6cd5\uff0c\u4f46\u5728\u67d0\u4e9b\u573a\u666f\u4e0b\u975e\u5e38\u6709\u7528\uff0c\u4f8b\u5982\u9700\u8981\u5408\u5e76\u4e24\u4e2a\u5b57\u5178\u6216\u66f4\u65b0\u73b0\u6709\u5b57\u5178\u4e2d\u7684\u952e\u503c\u5bf9\u3002<\/p>\n<\/p>\n
my_dict = {'name': 'Alice', 'age': 25}<\/p>\n
update_dict = {'age': 26, 'city': 'New York'}<\/p>\n
my_dict.update(update_dict)<\/p>\n
print(my_dict)  # \u8f93\u51fa: {'name': 'Alice', 'age': 26, 'city': 'New York'}<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u5408\u5e76\u5b57\u5178\u6216\u66f4\u65b0\u5b57\u5178\u4e2d\u7684\u952e\u503c\u5bf9\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u4e5d\u3001\u4f7f\u7528\u5b57\u5178\u7684copy()\u65b9\u6cd5<\/p>\n<\/p>\n
\u5b57\u5178\u7684copy()\u65b9\u6cd5\u53ef\u4ee5\u521b\u5efa\u4e00\u4e2a\u5b57\u5178\u7684\u6d45\u62f7\u8d1d\u3002\u867d\u7136\u8fd9\u4e0d\u662f\u76f4\u63a5\u83b7\u53d6\u952e\u503c\u7684\u65b9\u6cd5\uff0c\u4f46\u5728\u67d0\u4e9b\u573a\u666f\u4e0b\u975e\u5e38\u6709\u7528\uff0c\u4f8b\u5982\u9700\u8981\u5728\u4e0d\u4fee\u6539\u539f\u59cb\u5b57\u5178\u7684\u60c5\u51b5\u4e0b\u5904\u7406\u5b57\u5178\u3002<\/p>\n<\/p>\n
my_dict = {'name': 'Alice', 'age': 25, 'city': 'New York'}<\/p>\n
new_dict = my_dict.copy()<\/p>\n
print(new_dict)  # \u8f93\u51fa: {'name': 'Alice', 'age': 25, 'city': 'New York'}<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u521b\u5efa\u5b57\u5178\u7684\u526f\u672c\u4ee5\u907f\u514d\u5bf9\u539f\u59cb\u5b57\u5178\u8fdb\u884c\u4fee\u6539\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u5341\u3001\u4f7f\u7528\u5b57\u5178\u7684clear()\u65b9\u6cd5<\/p>\n<\/p>\n
\u5b57\u5178\u7684clear()\u65b9\u6cd5\u53ef\u4ee5\u6e05\u7a7a\u5b57\u5178\u4e2d\u7684\u6240\u6709\u952e\u503c\u5bf9\u3002\u867d\u7136\u8fd9\u4e0d\u662f\u76f4\u63a5\u83b7\u53d6\u952e\u503c\u7684\u65b9\u6cd5\uff0c\u4f46\u5728\u67d0\u4e9b\u573a\u666f\u4e0b\u975e\u5e38\u6709\u7528\uff0c\u4f8b\u5982\u9700\u8981\u91cd\u7f6e\u5b57\u5178\u3002<\/p>\n<\/p>\n
my_dict = {'name': 'Alice', 'age': 25, 'city': 'New York'}<\/p>\n
my_dict.clear()<\/p>\n
print(my_dict)  # \u8f93\u51fa: {}<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u6e05\u7a7a\u5b57\u5178\u4e2d\u7684\u6240\u6709\u952e\u503c\u5bf9\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u603b\u7ed3<\/p>\n<\/p>\n
\u901a\u8fc7\u4e0a\u8ff0\u65b9\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u8f7b\u677e\u5730\u5728Python\u4e2d\u83b7\u53d6\u5b57\u5178\u7684\u952e\u503c\u3002\u4f7f\u7528\u5b57\u5178\u7684keys()\u65b9\u6cd5\u662f\u6700\u5e38\u7528\u7684\u65b9\u5f0f\uff0c\u9002\u7528\u4e8e\u9700\u8981\u5feb\u901f\u83b7\u53d6\u6240\u6709\u952e\u503c\u7684\u60c5\u51b5<\/strong>\u3002\u4f7f\u7528for\u5faa\u73af\u904d\u5386\u5b57\u5178\u548c\u4f7f\u7528\u5b57\u5178\u7684items()\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u5bf9\u952e\u503c\u8fdb\u884c\u8fdb\u4e00\u6b65\u5904\u7406\u7684\u60c5\u51b5<\/strong>\u3002\u4f7f\u7528\u5b57\u5178\u7684get()\u65b9\u6cd5\u548csetdefault()\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u6839\u636e\u952e\u83b7\u53d6\u503c\u5e76\u8fdb\u884c\u8fdb\u4e00\u6b65\u5904\u7406\u7684\u60c5\u51b5<\/strong>\u3002\u4f7f\u7528\u5b57\u5178\u7684pop()\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u5728\u83b7\u53d6\u952e\u503c\u5bf9\u7684\u540c\u65f6\u4ece\u5b57\u5178\u4e2d\u5220\u9664\u8be5\u952e\u503c\u5bf9\u7684\u60c5\u51b5<\/strong>\u3002\u4f7f\u7528\u5b57\u5178\u7684fromkeys()\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u5feb\u901f\u521b\u5efa\u4e00\u4e2a\u5305\u542b\u7279\u5b9a\u952e\u7684\u5b57\u5178\u7684\u60c5\u51b5<\/strong>\u3002\u4f7f\u7528\u5b57\u5178\u7684update()\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u5408\u5e76\u5b57\u5178\u6216\u66f4\u65b0\u5b57\u5178\u4e2d\u7684\u952e\u503c\u5bf9\u7684\u60c5\u51b5<\/strong>\u3002\u4f7f\u7528\u5b57\u5178\u7684copy()\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u521b\u5efa\u5b57\u5178\u7684\u526f\u672c\u4ee5\u907f\u514d\u5bf9\u539f\u59cb\u5b57\u5178\u8fdb\u884c\u4fee\u6539\u7684\u60c5\u51b5<\/strong>\u3002\u4f7f\u7528\u5b57\u5178\u7684clear()\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u6e05\u7a7a\u5b57\u5178\u4e2d\u7684\u6240\u6709\u952e\u503c\u5bf9\u7684\u60c5\u51b5<\/strong>\u3002<\/p>\n<\/p>\n
\u901a\u8fc7\u719f\u7ec3\u638c\u63e1\u8fd9\u4e9b\u65b9\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u5904\u7406\u5b57\u5178\u65f6\u66f4\u52a0\u7075\u6d3b\u548c\u9ad8\u6548\u3002\u5e0c\u671b\u672c\u6587\u5bf9\u4f60\u5728Python\u7f16\u7a0b\u4e2d\u5904\u7406\u5b57\u5178\u952e\u503c\u6709\u6240\u5e2e\u52a9\u3002<\/p>\n<\/p>\n
\u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
 \u5982\u4f55\u5728Python\u4e2d\u83b7\u53d6\u5b57\u5178\u4e2d\u7684\u6240\u6709\u952e\u503c\uff1f<\/strong>
\u5728Python\u4e2d\uff0c\u53ef\u4ee5\u901a\u8fc7\u4f7f\u7528\u5b57\u5178\u7684keys()<\/code>\u65b9\u6cd5\u6765\u83b7\u53d6\u6240\u6709\u7684\u952e\u3002\u8fd9\u4e2a\u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a\u89c6\u56fe\u5bf9\u8c61\uff0c\u5305\u542b\u5b57\u5178\u4e2d\u6240\u6709\u7684\u952e\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a  <\/p>\n
my_dict = {'a': 1, 'b': 2, 'c': 3}\nkeys = my_dict.keys()\nprint(keys)  # \u8f93\u51fa\uff1adict_keys(['a', 'b', 'c'])\n<\/code><\/pre>\n
\u4f60\u8fd8\u53ef\u4ee5\u5c06\u5176\u8f6c\u6362\u4e3a\u5217\u8868\uff0c\u65b9\u4fbf\u8fdb\u4e00\u6b65\u5904\u7406\uff1a  <\/p>\n
keys_list = list(my_dict.keys())\nprint(keys_list)  # \u8f93\u51fa\uff1a['a', 'b', 'c']\n<\/code><\/pre>\n
\u5982\u4f55\u68c0\u67e5\u67d0\u4e2a\u952e\u5728\u5b57\u5178\u4e2d\u662f\u5426\u5b58\u5728\uff1f<\/strong>
\u8981\u786e\u5b9a\u4e00\u4e2a\u7279\u5b9a\u7684\u952e\u662f\u5426\u5b58\u5728\u4e8e\u5b57\u5178\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528in<\/code>\u5173\u952e\u5b57\u3002\u8fd9\u4e2a\u65b9\u6cd5\u7b80\u5355\u4e14\u9ad8\u6548\u3002\u4ee5\u4e0b\u662f\u793a\u4f8b\u4ee3\u7801\uff1a  <\/p>\n
my_dict = {'a': 1, 'b': 2, 'c': 3}\nkey_to_check = 'b'\nif key_to_check in my_dict:\n    print(f"\u952e {key_to_check} \u5b58\u5728\uff0c\u503c\u4e3a {my_dict[key_to_check]}")\nelse:\n    print(f"\u952e {key_to_check} \u4e0d\u5b58\u5728")\n<\/code><\/pre>\n
\u5728Python\u4e2d\u5982\u4f55\u83b7\u53d6\u5b57\u5178\u4e2d\u7279\u5b9a\u952e\u7684\u503c\uff1f<\/strong>
\u83b7\u53d6\u5b57\u5178\u4e2d\u67d0\u4e2a\u7279\u5b9a\u952e\u7684\u503c\u975e\u5e38\u7b80\u5355\u3002\u53ef\u4ee5\u901a\u8fc7\u76f4\u63a5\u4f7f\u7528\u65b9\u62ec\u53f7\u6216\u4f7f\u7528get()<\/code>\u65b9\u6cd5\u6765\u5b9e\u73b0\u3002\u4ee5\u4e0b\u662f\u4e24\u79cd\u65b9\u5f0f\u7684\u793a\u4f8b\uff1a  <\/p>\n
my_dict = {'a': 1, 'b': 2, 'c': 3}\n\n# \u4f7f\u7528\u65b9\u62ec\u53f7\nvalue = my_dict['a']\nprint(value)  # \u8f93\u51fa\uff1a1\n\n# \u4f7f\u7528get()\u65b9\u6cd5\nvalue = my_dict.get('b')\nprint(value)  # \u8f93\u51fa\uff1a2\n<\/code><\/pre>\n
\u4f7f\u7528get()<\/code>\u65b9\u6cd5\u7684\u597d\u5904\u5728\u4e8e\uff0c\u5982\u679c\u952e\u4e0d\u5b58\u5728\uff0c\u4e0d\u4f1a\u629b\u51fa\u9519\u8bef\uff0c\u800c\u662f\u8fd4\u56deNone<\/code>\u6216\u8005\u4f60\u6307\u5b9a\u7684\u9ed8\u8ba4\u503c\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"\u5728Python\u4e2d\uff0c\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u51e0\u79cd\u65b9\u5f0f\u6765\u83b7\u53d6\u5b57\u5178\u7684\u952e\u503c\uff1a\u4f7f\u7528\u5b57\u5178\u7684keys()\u65b9\u6cd5\u3001\u4f7f\u7528for\u5faa\u73af\u904d\u5386\u5b57\u5178\u3001\u4f7f […]","protected":false},"author":3,"featured_media":1064958,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1064952"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=1064952"}],"version-history":[{"count":"1","href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1064952\/revisions"}],"predecessor-version":[{"id":1064961,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1064952\/revisions\/1064961"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/1064958"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=1064952"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=1064952"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=1064952"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}