import timetry:f = open('test.txt')#尝试循环读取内容try:while True:con = f.readline()#如果读取完成退出循环if len(con) == 0:breaktime.sleep(3)print(con)except:#在命令提示符中如果按下Ctrl+c结束print("程序被意外终止")except:print('该文件不存在')自定义异常 在python中，抛出自定义异常的...
readline() if not text: # print(text is "") break else: # print(text == "\n") # 换行符不会被判定为空 print(text, end="") # 保留原文的换行,使print()的换行不起作用,因为print本身也是带有一个换行作用的 代码语言:javascript 代码运行次数:0 运行 AI代码解释 临江仙·滚滚长江东逝水滚滚...
During handling of the above exception, another exception occurred: NameError: name 'Error_var'is notdefined >>> 抛出异常 使用raise语句抛出一个异常 print(1)raiseZeroDivisionErrorprint(5) 运行结果: >>> 1ZeroDivisionError>>> 你需要声明你要抛出的例外名称。 抛出的异常可以用参数来指出这是什么错误。
f=open('myfile.txt') s=f.readline() i=int(s.strip()) exceptOSErroraserr: print("OS error: {0}".format(err)) exceptValueError: print("Could not convert data to an integer.") except: print("Unexpected error:",sys.exc_info()[0]) raise --- OSError 异常类型:操作系统错误 ValueErro...
NameError: name 'spam' is not defined >>> '2' + 2 # int 不能与 str 相加,触发异常 Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: can only concatenate str (not "int") to str 1. 2.
importsystry:f=open('myfile.txt')s=f.readline()i=int(s.strip())except OSErroraserr:print("OS error: {0}".format(err))except ValueError:print("Could not convert data to an integer.")except:print("Unexpected error:",sys.exc_info()[0])raise ...
s=f.readline() i=int(s.strip()) exceptOSErroraserr: print("OS error: {0}".format(err)) exceptValueError: print("Could not convert data to an integer.") except: print("Unexpected error:",sys.exc_info()[0]) raise try/except...else ...
s = f.readline() i = int(s.strip()) except OSError as err: print("OS error: {0}".format(err)) except ValueError: print("Could not convert data to an integer.") except: print("Unexpected error:", sys.exc_info()[0]) raise try ... except 语句有一个可选的 else 子句,在使用...
read() Traceback (most recent call last): File "<stdin>", line 1, in <module> IOError: File not open for reading #a模式也不支持read(),readline(),readlines() >>> file = open('test.txt','a') >>> print file.readline() Traceback (most recent call last): File "<stdin>", ...
>>> reload(sys) Traceback (most recent call last): File "<stdin>", line 1, in <module> NameError: name 'sys' is not defined 1. 2. 3. 4. 【 错误分析 】reload期望得到的是对象,所以该模块必须成功导入。在没导入模块前,不能重载. >>> import sys >>> reload(sys) <module 'sys' ...