如何获取要打印的变量输入？答案

【问题标题】：How do I get a variable input to print?如何获取要打印的变量输入？
【发布时间】：2018-08-22 00:36:58
【问题描述】：

我正在尝试获取要打印的课堂作业输入。

# Program Name: BadDate.py 
# Function:     This program determines if a date entered by the user is valid.  
# Input:        Interactive
# Output:       Valid date is printed or user is alerted that an invalid date was entered.

validDate = True
MIN_YEAR = 0
MIN_MONTH = 1
MAX_MONTH = 12
MIN_DAY = 1
MAX_DAY = 31

month = float (input("Enter Month "))
day = float (input("Enter Day "))
year = float (input("Enter Year "))


# Get the month, then the day, then the year
# housekeeping()

# Check to be sure date is valid

if int(year) <= MIN_YEAR: # invalid year
    validDate = False
elif int(month) < MIN_MONTH or int(month) > MAX_MONTH: # invalid month
    validDate = False
elif int(day) < MIN_DAY or int(day) > MAX_DAY: # invalid day
    validDate = False

# Test to see if date is valid and output date and whether it is valid or not
if validDate == True:
    print(str(month)+'/'+str(day)+'/'+str(year) " is a valid date") 
else:
    print(str(month)+'/'+str(day)+'/'+str(year) " is an invalid date")

# endOfJob()

当它到达日期时，它给了我一个语法错误。我需要这些语句来打印用户输入的日期。谢谢你。

【问题讨论】：

您在str(year) 和" is a ...date" 之间缺少+ 符号。应该是str(year) + " is a ...date"。

标签： python-3.x input printing

【解决方案1】：

如果您仔细查看给出的错误，您可能会发现它。现在，作为一个新用户，解码这些错误以及它们来自何处似乎具有挑战性。包含 SyntaxError 堆栈跟踪对您很有帮助，因此我们可以帮助您更快地向您展示问题所在。

无论如何，您只是在调用 print 函数时缺少 2 个简单的连接/加号运算符 (+)，所以这里是固定代码：

# Program Name: BadDate.py 
# Function:     This program determines if a date entered by the user is valid.  
# Input:        Interactive
# Output:       Valid date is printed or user is alerted that an invalid date was entered.

validDate = True
MIN_YEAR = 0
MIN_MONTH = 1
MAX_MONTH = 12
MIN_DAY = 1
MAX_DAY = 31

month = float (input("Enter Month "))
day = float (input("Enter Day "))
year = float (input("Enter Year "))


# Get the month, then the day, then the year
# housekeeping()

# Check to be sure date is valid

if int(year) <= MIN_YEAR: # invalid year
    validDate = False
elif int(month) < MIN_MONTH or int(month) > MAX_MONTH: # invalid month
    validDate = False
elif int(day) < MIN_DAY or int(day) > MAX_DAY: # invalid day
    validDate = False

# Test to see if date is valid and output date and whether it is valid or not
if validDate == True:
    print(str(month)+'/'+str(day)+'/'+str(year) + " is a valid date") 
else:
    print(str(month)+'/'+str(day)+'/'+str(year) + " is an invalid date")

# endOfJob()

【讨论】：

【解决方案2】：

您可以将所有这些组合成一个条件：

month = int(input("Enter Month "))
day = int (input("Enter Day "))
year = int (input("Enter Year "))
if 1<=day<=31 and year>0 and 1<=month<=12:
    print(str(month)+'/'+str(day)+'/'+str(year)+ " is a valid date") 
else:
    print(str(month)+'/'+str(day)+'/'+str(year) +" is an invalid date")

虽然如给定，但这意味着将Feb 30 02 之类的内容视为有效等

【讨论】：