Python PyScripter-导入argv错误
我正在使用“艰苦地学习Python”和PyScripter来编写和运行我的代码 在练习13中,我必须运行以下代码:Python PyScripter-导入argv错误,python,pyscripter,Python,Pyscripter,我正在使用“艰苦地学习Python”和PyScripter来编写和运行我的代码 在练习13中,我必须运行以下代码: from sys import argv script, first, second, third = argv print "The script is called:", script print "Your first variable is:", first print "Your second variable is:", second print "Your th
from sys import argv
script, first, second, third = argv
print "The script is called:", script
print "Your first variable is:", first
print "Your second variable is:", second
print "Your third variable is:", third
当我运行它时,我得到一个错误
ValueError: need more than 1 value to unpack
我读过关于同一主题的其他问题,似乎找不到有效的答案
我也很新的编码,所以解释如何做到这一点将是伟大的 只有向脚本传递三个命令行参数,脚本才能工作。例如:
script.py 1 2 3
您不能使用任何其他数量的命令行参数,否则将引发ValueError
也许您应该通过检查收到的参数数量,然后适当地分配名称第一个
,第二个
,和第三个
,使脚本更加健壮
下面是一个演示:
from sys import argv, exit
argc = len(argv) # Get the number of commandline arguments
if argc == 4:
# There were 3 commandline arguments
script, first, second, third = argv
elif argc == 3:
# There were only 2 commandline arguments
script, first, second = argv
third = '3rd'
elif argc == 2:
# There was only 1 commandline argument
script, first = argv
second = '2nd'
third = '3rd'
elif argc == 1:
# There was no commandline arguments
script = argv[0]
first = '1st'
second = '2nd'
third = '3rd'
else:
print "Too many commandline arguments"
exit(1)
print "The script is called:", script
print "Your first variable is:", first
print "Your second variable is:", second
print "Your third variable is:", third
当然,这只是一个例子。您可以在if语句中执行任何您想要的操作(将名称指定给不同的内容、引发异常、打印消息、退出脚本等)。这里最重要的部分是
argc=len(argv)
行和if语句,它们检查脚本接收到多少个参数。好的,我添加了您放在这里的内容,但是输出应该是,“脚本被调用:(无论保存在何处)”您的第一个变量是:first“您的第二个变量是:2nd”您的第三个变量是:3rd“但是我知道脚本名为:C:\Users\Justin\Desktop\Python\exerces\module13.py您的第一个变量是:None您的第二个变量是:None您的第三个变量是:None正如我所说,这只是一个示例。在if语句中,您可以做任何您想做的事情。但请看我的编辑。现在,它将名称None
指定给字符串。