{"id":1134162,"date":"2025-01-08T21:13:21","date_gmt":"2025-01-08T13:13:21","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/1134162.html"},"modified":"2025-01-08T21:13:24","modified_gmt":"2025-01-08T13:13:24","slug":"python%e5%9c%a8%e5%ad%97%e5%85%b8%e4%b8%ad%e5%a6%82%e4%bd%95%e6%89%be%e5%88%b0%e5%80%bc%e5%af%b9%e5%ba%94%e7%9a%84%e9%94%ae","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/1134162.html","title":{"rendered":"python\u5728\u5b57\u5178\u4e2d\u5982\u4f55\u627e\u5230\u503c\u5bf9\u5e94\u7684\u952e"},"content":{"rendered":"

\"python\u5728\u5b57\u5178\u4e2d\u5982\u4f55\u627e\u5230\u503c\u5bf9\u5e94\u7684\u952e\"<\/p>\n

\u5728Python\u4e2d\u627e\u5230\u5b57\u5178\u4e2d\u503c\u5bf9\u5e94\u7684\u952e\u7684\u65b9\u6cd5\u5305\u62ec\uff1a\u4f7f\u7528\u5faa\u73af\u904d\u5386\u5b57\u5178\u3001\u5b57\u5178\u63a8\u5bfc\u5f0f\u3001\u9006\u5411\u5b57\u5178\u7b49\u3002<\/strong>\u5176\u4e2d\uff0c\u6700\u5e38\u7528\u4e14\u76f4\u89c2\u7684\u65b9\u6cd5\u662f\u901a\u8fc7\u5faa\u73af\u904d\u5386\u5b57\u5178\u6765\u67e5\u627e\u503c\u5bf9\u5e94\u7684\u952e\u3002\u4e0b\u9762\u5c06\u8be6\u7ec6\u4ecb\u7ecd\u8fd9\u4e9b\u65b9\u6cd5\u53ca\u5176\u5e94\u7528\u573a\u666f\u3002<\/p>\n<\/p>\n

\u4e00\u3001\u4f7f\u7528\u5faa\u73af\u904d\u5386\u5b57\u5178<\/h3>\n<\/p>\n

\u4f7f\u7528\u5faa\u73af\u904d\u5386\u5b57\u5178\u662f\u6700\u76f4\u89c2\u7684\u65b9\u5f0f\u6765\u67e5\u627e\u503c\u5bf9\u5e94\u7684\u952e\u3002\u5728\u8fd9\u4e2a\u65b9\u6cd5\u4e2d\uff0c\u4f60\u4f1a\u904d\u5386\u5b57\u5178\u7684\u6bcf\u4e00\u4e2a\u952e\u503c\u5bf9\uff0c\u5e76\u68c0\u67e5\u503c\u662f\u5426\u5339\u914d\u3002\u5982\u679c\u5339\u914d\uff0c\u5219\u8fd4\u56de\u5bf9\u5e94\u7684\u952e\u3002<\/p>\n<\/p>\n

def find_key_by_value(d, value):<\/p>\n
    for k, v in d.items():<\/p>\n
        if v == value:<\/p>\n
            return k<\/p>\n
    return None  # \u5982\u679c\u6ca1\u6709\u627e\u5230\u5bf9\u5e94\u7684\u952e\u5219\u8fd4\u56deNone<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u4e2a\u65b9\u6cd5\u9002\u7528\u4e8e\u5b57\u5178\u4e2d\u6ca1\u6709\u91cd\u590d\u503c\u7684\u60c5\u51b5\u3002\u5982\u679c\u5b57\u5178\u4e2d\u6709\u591a\u4e2a\u952e\u5bf9\u5e94\u76f8\u540c\u7684\u503c\uff0c\u53ef\u80fd\u9700\u8981\u8fd4\u56de\u4e00\u4e2a\u5305\u542b\u6240\u6709\u5339\u914d\u952e\u7684\u5217\u8868\u3002<\/p>\n<\/p>\n
def find_keys_by_value(d, value):<\/p>\n
    keys = [k for k, v in d.items() if v == value]<\/p>\n
    return keys if keys else None<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u4e8c\u3001\u4f7f\u7528\u5b57\u5178\u63a8\u5bfc\u5f0f<\/h3>\n<\/p>\n
\u5b57\u5178\u63a8\u5bfc\u5f0f\u662fPython\u4e2d\u4e00\u79cd\u5f3a\u5927\u7684\u5de5\u5177\uff0c\u53ef\u4ee5\u7528\u6765\u521b\u5efa\u65b0\u7684\u5b57\u5178\u6216\u5217\u8868\u3002\u901a\u8fc7\u5b57\u5178\u63a8\u5bfc\u5f0f\uff0c\u6211\u4eec\u53ef\u4ee5\u7b80\u5316\u67e5\u627e\u8fc7\u7a0b\u3002<\/p>\n<\/p>\n
def find_keys_by_value_comprehension(d, value):<\/p>\n
    return [k for k, v in d.items() if v == value]<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u4e0e\u4e0a\u8ff0\u65b9\u6cd5\u7c7b\u4f3c\uff0c\u4f46\u5728\u4ee3\u7801\u4e0a\u66f4\u52a0\u7b80\u6d01\u3002\u5b83\u540c\u6837\u9002\u7528\u4e8e\u5b57\u5178\u4e2d\u6709\u91cd\u590d\u503c\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u4e09\u3001\u9006\u5411\u5b57\u5178<\/h3>\n<\/p>\n
\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\uff0c\u4f60\u53ef\u80fd\u9700\u8981\u9891\u7e41\u5730\u67e5\u627e\u503c\u5bf9\u5e94\u7684\u952e\u3002\u8fd9\u65f6\uff0c\u521b\u5efa\u4e00\u4e2a\u9006\u5411\u5b57\u5178\uff08\u5373\u952e\u548c\u503c\u4e92\u6362\uff09\u4f1a\u662f\u4e00\u4e2a\u9ad8\u6548\u7684\u89e3\u51b3\u65b9\u6848\u3002<\/p>\n<\/p>\n
def invert_dict(d):<\/p>\n
    return {v: k for k, v in d.items()}<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u6709\u4e86\u9006\u5411\u5b57\u5178\u540e\uff0c\u4f60\u53ef\u4ee5\u901a\u8fc7\u67e5\u627e\u952e\u6765\u83b7\u53d6\u539f\u6765\u7684\u503c\u3002<\/p>\n<\/p>\n
inverse_d = invert_dict(d)<\/p>\n
key = inverse_d.get(value)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u56db\u3001\u4f7f\u7528\u5185\u7f6e\u51fd\u6570\u548c\u5e93<\/h3>\n<\/p>\n
Python\u6807\u51c6\u5e93\u548c\u7b2c\u4e09\u65b9\u5e93\u63d0\u4f9b\u4e86\u4e00\u4e9b\u5de5\u5177\uff0c\u53ef\u4ee5\u5e2e\u52a9\u4f60\u66f4\u65b9\u4fbf\u5730\u67e5\u627e\u503c\u5bf9\u5e94\u7684\u952e\u3002\u4f8b\u5982\uff0cpandas<\/code>\u5e93\u4e2d\u7684Series<\/code>\u5bf9\u8c61\u5c31\u6709\u4e00\u4e2aidxmax<\/code>\u65b9\u6cd5\uff0c\u53ef\u4ee5\u7528\u6765\u67e5\u627e\u6700\u5927\u503c\u5bf9\u5e94\u7684\u7d22\u5f15\u3002<\/p>\n<\/p>\n
import pandas as pd<\/p>\n
def find_key_by_value_pandas(d, value):<\/p>\n
    series = pd.Series(d)<\/p>\n
    return series[series == value].index.tolist()<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u4e94\u3001\u6027\u80fd\u8003\u8651<\/h3>\n<\/p>\n
\u5728\u5904\u7406\u5927\u6570\u636e\u96c6\u65f6\uff0c\u6027\u80fd\u95ee\u9898\u53ef\u80fd\u4f1a\u53d8\u5f97\u5c24\u4e3a\u91cd\u8981\u3002\u5faa\u73af\u904d\u5386\u5b57\u5178\u5728\u65f6\u95f4\u590d\u6742\u5ea6\u4e0a\u662fO(n)\uff0c\u800c\u521b\u5efa\u9006\u5411\u5b57\u5178\u5219\u9700\u8981\u989d\u5916\u7684\u7a7a\u95f4\u590d\u6742\u5ea6\u3002\u56e0\u6b64\uff0c\u5728\u9009\u62e9\u65b9\u6cd5\u65f6\u9700\u8981\u6839\u636e\u5177\u4f53\u7684\u5e94\u7528\u573a\u666f\u8fdb\u884c\u6743\u8861\u3002<\/p>\n<\/p>\n
\u516d\u3001\u9519\u8bef\u5904\u7406\u548c\u8fb9\u754c\u60c5\u51b5<\/h3>\n<\/p>\n
\u5728\u7f16\u5199\u51fd\u6570\u65f6\uff0c\u8003\u8651\u5230\u5404\u79cd\u53ef\u80fd\u7684\u8fb9\u754c\u60c5\u51b5\u548c\u9519\u8bef\u5904\u7406\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002\u4f8b\u5982\uff0c\u5f53\u5b57\u5178\u4e3a\u7a7a\u6216\u503c\u5728\u5b57\u5178\u4e2d\u4e0d\u5b58\u5728\u65f6\uff0c\u9700\u8981\u9002\u5f53\u7684\u5904\u7406\u3002<\/p>\n<\/p>\n
def find_key_by_value_SAFe<\/a>(d, value):<\/p>\n
    if not d:  # \u68c0\u67e5\u5b57\u5178\u662f\u5426\u4e3a\u7a7a<\/p>\n
        return None<\/p>\n
    keys = [k for k, v in d.items() if v == value]<\/p>\n
    return keys if keys else None<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u4e03\u3001\u5e94\u7528\u5b9e\u4f8b<\/h3>\n<\/p>\n
1. \u67e5\u627e\u5b66\u751f\u6210\u7ee9\u5bf9\u5e94\u7684\u59d3\u540d<\/h4>\n<\/p>\n
\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u5b66\u751f\u6210\u7ee9\u7684\u5b57\u5178\uff0c\u60f3\u8981\u67e5\u627e\u67d0\u4e2a\u7279\u5b9a\u6210\u7ee9\u5bf9\u5e94\u7684\u5b66\u751f\u59d3\u540d\u3002<\/p>\n<\/p>\n
grades = {<\/p>\n
    'Alice': 85,<\/p>\n
    'Bob': 95,<\/p>\n
    'Charlie': 85,<\/p>\n
    'David': 90<\/p>\n
}<\/p>\n
students_with_85 = find_keys_by_value(grades, 85)<\/p>\n
print(students_with_85)  # \u8f93\u51fa: ['Alice', 'Charlie']<\/p>\n
<\/code><\/pre>\n<\/p>\n
2. \u67e5\u627e\u4ea7\u54c1\u4ef7\u683c\u5bf9\u5e94\u7684\u4ea7\u54c1\u540d\u79f0<\/h4>\n<\/p>\n
\u5728\u4e00\u4e2a\u7535\u5546\u5e73\u53f0\u4e0a\uff0c\u6211\u4eec\u53ef\u80fd\u9700\u8981\u67e5\u627e\u67d0\u4e2a\u4ef7\u683c\u5bf9\u5e94\u7684\u6240\u6709\u4ea7\u54c1\u540d\u79f0\u3002<\/p>\n<\/p>\n
products = {<\/p>\n
    'Laptop': 1000,<\/p>\n
    'Smartphone': 800,<\/p>\n
    'Tablet': 600,<\/p>\n
    'Smartwatch': 200<\/p>\n
}<\/p>\n
products_with_800 = find_keys_by_value_comprehension(products, 800)<\/p>\n
print(products_with_800)  # \u8f93\u51fa: ['Smartphone']<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u516b\u3001\u603b\u7ed3<\/h3>\n<\/p>\n
\u5728Python\u4e2d\u67e5\u627e\u5b57\u5178\u4e2d\u503c\u5bf9\u5e94\u7684\u952e\u6709\u591a\u79cd\u65b9\u6cd5\uff0c\u5305\u62ec\u4f7f\u7528\u5faa\u73af\u904d\u5386\u5b57\u5178\u3001\u5b57\u5178\u63a8\u5bfc\u5f0f\u3001\u9006\u5411\u5b57\u5178\u548c\u5185\u7f6e\u51fd\u6570\u5e93\u3002\u6bcf\u79cd\u65b9\u6cd5\u90fd\u6709\u5176\u4f18\u7f3a\u70b9\u548c\u9002\u7528\u573a\u666f\u3002\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u5e94\u6839\u636e\u5177\u4f53\u9700\u6c42\u548c\u6570\u636e\u89c4\u6a21\u9009\u62e9\u5408\u9002\u7684\u65b9\u6cd5\u3002\u6b64\u5916\uff0c\u8003\u8651\u8fb9\u754c\u60c5\u51b5\u548c\u9519\u8bef\u5904\u7406\u4e5f\u662f\u7f16\u5199\u5065\u58ee\u4ee3\u7801\u7684\u91cd\u8981\u90e8\u5206\u3002<\/p>\n<\/p>\n
\u901a\u8fc7\u5bf9\u8fd9\u4e9b\u65b9\u6cd5\u7684\u638c\u63e1\u548c\u7075\u6d3b\u8fd0\u7528\uff0c\u4f60\u53ef\u4ee5\u66f4\u9ad8\u6548\u5730\u5904\u7406\u5b57\u5178\u6570\u636e\uff0c\u63d0\u5347\u4ee3\u7801\u7684\u53ef\u8bfb\u6027\u548c\u6027\u80fd\u3002\u5e0c\u671b\u8fd9\u7bc7\u6587\u7ae0\u5bf9\u4f60\u6709\u6240\u5e2e\u52a9\uff0c\u80fd\u5728\u4f60\u7684Python\u7f16\u7a0b\u65c5\u7a0b\u4e2d\u63d0\u4f9b\u5b9e\u7528\u7684\u6307\u5bfc\u3002<\/p>\n<\/p>\n
\u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
 \u5982\u4f55\u5728Python\u5b57\u5178\u4e2d\u5feb\u901f\u67e5\u627e\u7279\u5b9a\u503c\u5bf9\u5e94\u7684\u952e\uff1f<\/strong>
\u5728Python\u4e2d\uff0c\u5b57\u5178\u662f\u4ee5\u952e\u503c\u5bf9\u7684\u5f62\u5f0f\u5b58\u50a8\u6570\u636e\u7684\u3002\u5982\u679c\u60a8\u60f3\u8981\u67e5\u627e\u4e00\u4e2a\u7279\u5b9a\u503c\u5bf9\u5e94\u7684\u952e\uff0c\u53ef\u4ee5\u4f7f\u7528\u5217\u8868\u63a8\u5bfc\u5f0f\u6765\u5b9e\u73b0\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a  <\/p>\n
my_dict = {'a': 1, 'b': 2, 'c': 3}\nkey = [k for k, v in my_dict.items() if v == 2]\nprint(key)  # \u8f93\u51fa ['b']\n<\/code><\/pre>\n
\u8fd9\u79cd\u65b9\u6cd5\u4f1a\u8fd4\u56de\u6240\u6709\u4e0e\u6307\u5b9a\u503c\u5339\u914d\u7684\u952e\u5217\u8868\u3002<\/p>\n
\u5982\u679c\u5b57\u5178\u4e2d\u6709\u591a\u4e2a\u76f8\u540c\u503c\uff0c\u8be5\u5982\u4f55\u5904\u7406\uff1f<\/strong>
\u5728Python\u5b57\u5178\u4e2d\uff0c\u591a\u4e2a\u952e\u53ef\u4ee5\u5bf9\u5e94\u76f8\u540c\u7684\u503c\u3002\u5f53\u4f7f\u7528\u4e0a\u8ff0\u65b9\u6cd5\u67e5\u627e\u952e\u65f6\uff0c\u6240\u6709\u4e0e\u8be5\u503c\u5339\u914d\u7684\u952e\u90fd\u4f1a\u88ab\u8fd4\u56de\u3002\u5982\u679c\u53ea\u60f3\u8981\u7b2c\u4e00\u4e2a\u5339\u914d\u7684\u952e\uff0c\u53ef\u4ee5\u5c06\u5217\u8868\u63a8\u5bfc\u5f0f\u4fee\u6539\u4e3a\uff1a  <\/p>\n
key = next((k for k, v in my_dict.items() if v == 2), None)\n<\/code><\/pre>\n
\u8fd9\u6837\uff0c\u60a8\u5c06\u5f97\u5230\u7b2c\u4e00\u4e2a\u4e0e\u8be5\u503c\u5339\u914d\u7684\u952e\uff0c\u5982\u679c\u6ca1\u6709\u627e\u5230\u5219\u8fd4\u56deNone\u3002<\/p>\n
\u5728\u5b57\u5178\u4e2d\u67e5\u627e\u503c\u5bf9\u5e94\u7684\u952e\u65f6\uff0c\u6709\u6ca1\u6709\u6027\u80fd\u8003\u8651\uff1f<\/strong>
\u5f53\u5b57\u5178\u975e\u5e38\u5927\u65f6\uff0c\u67e5\u627e\u503c\u5bf9\u5e94\u7684\u952e\u53ef\u80fd\u4f1a\u53d8\u5f97\u6bd4\u8f83\u8017\u65f6\uff0c\u56e0\u4e3a\u9700\u8981\u904d\u5386\u6574\u4e2a\u5b57\u5178\u3002\u4e3a\u4e86\u63d0\u9ad8\u6027\u80fd\uff0c\u53ef\u4ee5\u8003\u8651\u521b\u5efa\u4e00\u4e2a\u53cd\u5411\u5b57\u5178\uff0c\u5c06\u503c\u6620\u5c04\u5230\u952e\uff0c\u8fd9\u6837\u67e5\u627e\u7684\u65f6\u95f4\u590d\u6742\u5ea6\u5c06\u964d\u4f4e\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a  <\/p>\n
reverse_dict = {v: k for k, v in my_dict.items()}\nkey = reverse_dict.get(2)  # \u76f4\u63a5\u67e5\u627e\u503c\u5bf9\u5e94\u7684\u952e\n<\/code><\/pre>\n
\u8fd9\u79cd\u65b9\u6cd5\u5728\u9891\u7e41\u67e5\u627e\u7684\u573a\u666f\u4e2d\u4f1a\u66f4\u52a0\u9ad8\u6548\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"\u5728Python\u4e2d\u627e\u5230\u5b57\u5178\u4e2d\u503c\u5bf9\u5e94\u7684\u952e\u7684\u65b9\u6cd5\u5305\u62ec\uff1a\u4f7f\u7528\u5faa\u73af\u904d\u5386\u5b57\u5178\u3001\u5b57\u5178\u63a8\u5bfc\u5f0f\u3001\u9006\u5411\u5b57\u5178\u7b49\u3002\u5176\u4e2d\uff0c\u6700\u5e38\u7528\u4e14\u76f4\u89c2\u7684 […]","protected":false},"author":3,"featured_media":1134171,"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\/1134162"}],"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=1134162"}],"version-history":[{"count":"1","href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1134162\/revisions"}],"predecessor-version":[{"id":1134174,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1134162\/revisions\/1134174"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/1134171"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=1134162"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=1134162"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=1134162"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}