在Python開發過程中，經常會遇到各種各樣的報錯情況，所以瞭解Python中的各種報錯就很有必要。小白最近整理了一下Python中經常遇到的報錯情況，並列舉了案例，如下表格，還有一些報錯情況，待嘗試~
| AssertionError | 斷言語句失敗：當 assert 關鍵字後的條件爲假時，程序運行會停止並拋出 AssertionError 異常 | l1 = ['111a'] assert len(l1)>0 l2 = [] assert len(l2)>0 --------------------------------------------------------------------------- AssertionError Traceback (most recent call last) <ipython-input-4-5d421c3e78d3> in <module> 1 l2 = [] ----> 2 assert len(l2)>0 |
| IndexError | 序列中沒有此索引(index):索引超出序列範圍會引發此異常 | l1 = ['111a'] l1[1] --------------------------------------------------------------------------- IndexError Traceback (most recent call last) <ipython-input-5-130763729f9e> in <module> 1 l1 = ['111a'] ----> 2 l1[1] IndexError: list index out of range |
| KeyError | 映射中沒有這個鍵:字典中查找一個不存在的關鍵字時引發此異常 | dict={'張三':"50"} dict["李四"] --------------------------------------------------------------------------- KeyError Traceback (most recent call last) <ipython-input-9-77ca0e0db50c> in <module> 1 dict={'張三':"50"} ----> 2 dict["李四"] KeyError: '李四' |
| AttributeError | 對象沒有這個屬性:當試圖訪問的對象屬性不存在時拋出的異常 | l1 = ['111a'] l1.len --------------------------------------------------------------------------- AttributeError Traceback (most recent call last) <ipython-input-10-f1db6a9cf562> in <module> 1 l1 = ['111a'] ----> 2 l1.len AttributeError: 'list' object has no attribute 'len' |
| NameError | 未聲明/初始化對象 (沒有屬性):嘗試訪問一個未聲明的變量時，引發此異常 | l1 = ['111a'] l2 = [] l3 --------------------------------------------------------------------------- NameError Traceback (most recent call last) <ipython-input-13-75536776ce4c> in <module> 1 l1 = ['111a'] 2 l2 = [] ----> 3 l3 NameError: name 'l3' is not defined |
| TypeError | 對類型無效的操作:不同類型數據之間的無效操作 | 1+'aaa --------------------------------------------------------------------------- TypeError Traceback (most recent call last) <ipython-input-14-9e5eb69813e3> in <module> ----> 1 1+'aaa' TypeError: unsupported operand type(s) for +: 'int' and 'str' |
| ZeroDivisionError | 除(或取模)零 (所有數據類型)：除法運算中除數爲 0 引發此異常 | a = 1/0 --------------------------------------------------------------------------- ZeroDivisionError Traceback (most recent call last) <ipython-input-15-6c16767f6731> in <module> ----> 1 a = 1/0 ZeroDivisionError: division by zero |
| StopIteration | 迭代器沒有更多的值 | iterable = iter([1,2]) print(next(iterable)) print(next(iterable)) print(next(iterable)) 1 2 --------------------------------------------------------------------------- StopIteration Traceback (most recent call last) <ipython-input-16-0f9614553e6f> in <module> 2 print(next(iterable)) 3 print(next(iterable)) ----> 4 print(next(iterable)) StopIteration: |
| ImportError | 導入模塊/對象失敗 | import sy --------------------------------------------------------------------------- ModuleNotFoundError Traceback (most recent call last) <ipython-input-29-1afd4de6e860> in <module> ----> 1 import sy ModuleNotFoundError: No module named 'sy' |
| SyntaxError | Python 語法錯誤 | for i in range(0,10)): File "<ipython-input-30-3edb23e8bd2e>", line 1 for i in range(0,10)): ^ SyntaxError: invalid syntax |
| ValueError | 傳入無效的參數 | #range方法的第三個參數不可爲0 for i in range(1, 3, 0): print (i) --------------------------------------------------------------------------- ValueError Traceback (most recent call last) <ipython-input-35-3663a22f4899> in <module> ----> 1 for i in range(1, 3, 0): 2 print (i) ValueError: range() arg 3 must not be zero |
| BaseException | 所有異常的基類 | |
| SystemExit | 解釋器請求退出 | |
| KeyboardInterrupt | 用戶中斷執行(通常是輸入^C) | |
| Exception | 常規錯誤的基類 | |
| GeneratorExit | 生成器(generator)發生異常來通知退出 | |
| StandardError | 所有的內建標準異常的基類 | |
| ArithmeticError | 所有數值計算錯誤的基類 | |
| FloatingPointError | 浮點計算錯誤 | |
| OverflowError | 數值運算超出最大限制 | |
| EOFError | 沒有內建輸入,到達EOF 標記 | |
| EnvironmentError | 操作系統錯誤的基類 | |
| IOError | 輸入/輸出操作失敗 | |
| OSError | 操作系統錯誤 | |
| WindowsError | 系統調用失敗 | |
| LookupError | 無效數據查詢的基類 | |
| MemoryError | 內存溢出錯誤(對於Python 解釋器不是致命的) | |
| UnboundLocalError | 訪問未初始化的本地變量 | |
| ReferenceError | 弱引用(Weak reference)試圖訪問已經垃圾回收了的對象 | |
| RuntimeError | 一般的運行時錯誤 | |
| NotImplementedError | 尚未實現的方法 | |
| IndentationError | 縮進錯誤 | |
| TabError | Tab 和空格混用 | |
| SystemError | 一般的解釋器系統錯誤 | |
| UnicodeError | Unicode 相關的錯誤 | |
| UnicodeDecodeError | Unicode 解碼時的錯誤 | |
| UnicodeEncodeError | Unicode 編碼時錯誤 | |
| UnicodeTranslateError | Unicode 轉換時錯誤 | |
| Warning | 警告的基類 | |
| DeprecationWarning | 關於被棄用的特徵的警告 | |
| FutureWarning | 關於構造將來語義會有改變的警告 | |
| OverflowWarning | 舊的關於自動提升爲長整型(long)的警告 | |
| PendingDeprecationWarning | 關於特性將會被廢棄的警告 | |
| RuntimeWarning | 可疑的運行時行爲(runtime behavior)的警告 | |
| SyntaxWarning | 可疑的語法的警告 | |
| UserWarning | 用戶代碼生成的警告 |
爲了更加系統的瞭解報錯的層級情況，下面列出Python中錯誤的層級結構，以下是 Python 內置異常類的層次結構：
BaseException
+-- SystemExit
+-- KeyboardInterrupt
+-- GeneratorExit
+-- Exception
+-- StopIteration
+-- ArithmeticError
| +-- FloatingPointError
| +-- OverflowError
| +-- ZeroDivisionError
+-- AssertionError
+-- AttributeError
+-- BufferError
+-- EOFError
+-- ImportError
+-- LookupError
| +-- IndexError
| +-- KeyError
+-- MemoryError
+-- NameError
| +-- UnboundLocalError
+-- OSError
| +-- BlockingIOError
| +-- ChildProcessError
| +-- ConnectionError
| | +-- BrokenPipeError
| | +-- ConnectionAbortedError
| | +-- ConnectionRefusedError
| | +-- ConnectionResetError
| +-- FileExistsError
| +-- FileNotFoundError
| +-- InterruptedError
| +-- IsADirectoryError
| +-- NotADirectoryError
| +-- PermissionError
| +-- ProcessLookupError
| +-- TimeoutError
+-- ReferenceError
+-- RuntimeError
| +-- NotImplementedError
+-- SyntaxError
| +-- IndentationError
| +-- TabError
+-- SystemError
+-- TypeError
+-- ValueError
| +-- UnicodeError
| +-- UnicodeDecodeError
| +-- UnicodeEncodeError
| +-- UnicodeTranslateError
+-- Warning
+-- DeprecationWarning
+-- PendingDeprecationWarning
+-- RuntimeWarning
+-- SyntaxWarning
+-- UserWarning
+-- FutureWarning
+-- ImportWarning
+-- UnicodeWarning
+-- BytesWarning
+-- ResourceWarning
