所以我试图让全局变量在For循环中使用。不在函数中时,此代码可以正常运行" def"但我需要它,因为我试图创建一个tkinter文件对话框,如果你可以帮助告诉我我做错了什么或给我一个替代使用tkinter和" DEF&#34 ;.
工作代码:
import os
import sqlite3
from datetime import datetime
# import datetime
import itertools
from dateutil.relativedelta import relativedelta
date = datetime.strptime('1991-01-01', '%Y-%m-%d')
f_path = 'C:/Users/Lewis Collins/Job_Code/data/cru_ts_2_10.1991-2000_cutdown.pre'
# db = sqlite3.connect('output.db')
# cursor = db.cursor()
# cursor.execute('CREATE TABLE Rainfall (Xref, Yref, Date, Value)')
# date = datetime.date(1991,1,1)
flag = 0
Xref = ''
Yref = ''
with open(f_path) as file_read:
for row in itertools.islice(file_read, 5, None):
# print(row)
if 'Grid-ref' in row:
Xref = row.split(',')[0].split('= ')[1]
Yref = row.split(',')[1]
date = datetime.strptime('1990-12-01', '%Y-%m-%d')
else:
for Value in row.split():
date = date + relativedelta(months=+1)
# print(Xref.strip(), Yref.strip(), date, Value)
# print(Xref, Yref, date, Value)
# db.commit()
# db.close()
编辑代码:
import tkinter
from datetime import datetime
from dateutil.relativedelta import relativedelta
import itertools
#date = datetime.strptime('1991-01-01', '%y-%m-%d')
# date = datetime.strptime('1991-01-01', '%Y-%m-%d')
f_path = 'C:/Users/Lewis Collins/Job_Code/data/cru_ts_2_10.1991-2000_cutdown.pre'
Xref = ''
Yref = ''
def read_date():
with open(f_path) as file_read:
for row in itertools.islice(file_read, 5, None):
if 'Grid-ref' in row:
Xref = row.split(',')[0].split('= ')[1]
Yref = row.split(',')[1]
date = datetime.strptime('1990-12-01', '%y-%m-%d')
else:
for Value in row.split():
date = date + relativedelta(months=+1)
print(Xref.strip(), Yref.strip(), date, Value)
答案 0 :(得分:0)
不推荐使用全局变量的PS仅在最后一种方式使用它们
在你的函数中添加全局关键字,如下所示
my_blobal_var
my_blobal_var2
def my_func():
global my_blobal_var
global my_blobal_var2
do_something()
适合您的情况
Xref = ''
Yref = ''
def read_date():
global Xref
global Yref
do_your_thing()
答案 1 :(得分:0)
不要使用全局变量。这几乎总是一个错误。将参数传递给函数并让它返回结果:
def read_date(path):
xref = ''
yref = ''
with open(path) as file_read:
for row in itertools.islice(file_read, 5, None):
if 'Grid-ref' in row:
xref = row.split(',')[0].split('= ')[1]
yref = row.split(',')[1]
date = datetime.strptime('1990-12-01', '%y-%m-%d')
else:
for Value in row.split():
date = date + relativedelta(months=+1)
print(Xref.strip(), Yref.strip(), date, Value)
return xref, yref, date, Value
这样,xref
,yref
,...是read_date
函数中的局部变量。完成后,它会将其值返回给调用者。它还将文件路径作为参数,而不是将其绑定到全局变量。你会这样称呼它:
Xref, Yref, date, Value = read_date(f_path)
注意:您的代码示例中不清楚实际有用的数据。只需返回您关注的任何结果,并在调用该函数时以相同的顺序收集它们。