try:
    # 可能會拋出異常的代碼
except SomeException as e:
    # 捕獲并處理異常
else:
    # 如果 try 中代碼沒有異常，就執(zhí)行這里
finally:
    # 無論是否發(fā)生異常，最后都會執(zhí)行這里

try:
    x = int("abc")  # 會觸發(fā) ValueError
except ValueError:
    print("捕獲到 ValueError")
except TypeError:
    print("捕獲到 TypeError")

try:
    result = 10 / 2
except ZeroDivisionError:
    print("除零錯誤")
else:
    print("計算成功，結(jié)果是：", result)

try:
    f = open("test.txt", "r")
    data = f.read()
except FileNotFoundError:
    print("文件不存在")
else:
    print("讀取成功")
finally:
    print("執(zhí)行 finally")
    if 'f' in locals() and not f.closed:
        f.close()

try:
    x = int("abc")
except ValueError:
    print("數(shù)值錯誤")
except Exception as e:
    print("其他異常:", e)

try:
    x = int("abc")
except (ValueError, TypeError) as e:
    print("捕獲到異常:", e)

try:
    num = int("123")
except ValueError:
    print("轉(zhuǎn)換失敗")
else:
    print("轉(zhuǎn)換成功，結(jié)果是:", num)

try:
    f = open("data.txt", "r")
    data = f.read()
except FileNotFoundError:
    print("文件沒找到")
finally:
    print("關閉文件")
    if 'f' in locals() and not f.closed:
        f.close()

def foo():
    try:
        return 1
    finally:
        return 2

print(foo())  # 輸出 2，而不是 1

try:
    f = open("test.txt", "r")
    data = f.read()
except FileNotFoundError:
    print("文件不存在")
else:
    print("文件內(nèi)容：", data)
finally:
    if 'f' in locals() and not f.closed:
        f.close()
        print("文件已關閉")

try:
    num = int(input("請輸入一個整數(shù): "))
except ValueError:
    print("輸入無效，請輸入整數(shù)！")
else:
    print("你輸入的整數(shù)是:", num)

import requests

try:
    response = requests.get("https://httpbin.org/get")
    data = response.json()
except requests.RequestException as e:
    print("請求失敗:", e)
else:
    print("請求成功，返回數(shù)據(jù):", data)
finally:
    print("請求結(jié)束")

try:
    x = int("abc")  # ValueError
    y = 10 / 0      # ZeroDivisionError
except ValueError:
    print("數(shù)值轉(zhuǎn)換錯誤")
except ZeroDivisionError:
    print("除零錯誤")
except Exception as e:
    print("其他錯誤:", e)

class FakeDB:
    def connect(self): print("連接數(shù)據(jù)庫")
    def close(self): print("關閉數(shù)據(jù)庫")
    def query(self): return [1, 2, 3]

db = FakeDB()
try:
    db.connect()
    result = db.query()
except Exception as e:
    print("查詢失敗:", e)
else:
    print("查詢結(jié)果:", result)
finally:
    db.close()

import os

try:
    with open("temp.txt", "w") as f:
        f.write("臨時數(shù)據(jù)")
    raise RuntimeError("模擬出錯")
except RuntimeError as e:
    print("捕獲到異常:", e)
finally:
    if os.path.exists("temp.txt"):
        os.remove("temp.txt")
        print("臨時文件已刪除")

def process_data(data):
    try:
        return int(data)
    except ValueError as e:
        print("日志記錄：數(shù)據(jù)轉(zhuǎn)換失敗 ->", e)
        raise   # 重新拋出異常，讓上層調(diào)用者知道

class DataFormatError(Exception):
    pass

def load_data(data):
    if not isinstance(data, dict):
        raise DataFormatError("數(shù)據(jù)必須是字典類型")

try:
    load_data("not_dict")
except DataFormatError as e:
    print("捕獲到自定義異常:", e)

class Demo:
    def __enter__(self):
        print("進入上下文")
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        print("退出上下文")
        if exc_type:
            print("捕獲異常:", exc_type, exc_val)
            return True  # 返回 True 表示異常已處理，不會再拋出

with Demo():
    print("運行中...")
    raise ValueError("測試異常")
print("程序繼續(xù)執(zhí)行")

try:
    f = open("config.json")
    config = f.read()
except FileNotFoundError:
    print("配置文件缺失")
else:
    print("配置文件加載成功")
finally:
    if 'f' in locals():
        f.close()

def test():
    try:
        1 / 0
    except ZeroDivisionError:
        print("捕獲到異常")
        raise
    finally:
        return "finally 覆蓋了異常"

print(test())  # 輸出 "finally 覆蓋了異常"

import contextlib

with contextlib.suppress(FileNotFoundError):
    with open("no_such_file.txt") as f:
        data = f.read()

print("即使文件不存在，程序也能繼續(xù)運行")

try:
    db.begin()
    db.insert("users", {"id": 1, "name": "Alice"})
    db.commit()
except Exception as e:
    db.rollback()
    print("事務失敗:", e)

import threading

def worker():
    try:
        1 / 0
    except Exception as e:
        print("子線程異常:", e)

t = threading.Thread(target=worker)
t.start()
t.join()