以下是csv文件的摘录。第一列是产品编号，2是库存水平，3是目标水平，4是距目标的距离（目标减去库存水平。）
$VAR1 = [
{ 'total' => '2',
'results' => [
{ 'contact_type_name' => 'Primary Technical Contact',
'street' => undef,
'state_id' => undef,
'state_name' => undef,
'last_name' => 'Barb',
'entities' => [
{ 'entity_name' => 'XXXXX',
'entity_id' => 'XXXXX'
}
],
'state_abbr_name' => undef,
'city' => undef,
'country_id' => undef,
'latitude' => undef,
'contact_id' => 'XXXXXX',
'contact_type_id' => '1',
'roles' => [],
'contact_methods' => [
{ 'entity_name' => undef,
'contact_method_value' => 'XXXXXXX',
'contact_method_type_id' => '4',
'contact_method_id' => '24041',
'entity_id' => undef,
'contact_method_type_name' => 'Cell Phone'
},
{ 'entity_name' => undef,
'contact_method_value' => 'XXXXXX',
'contact_method_type_id' => '2',
'contact_method_id' => '24051',
'entity_id' => undef,
'contact_method_type_name' => 'Office Phone'
},
{ 'entity_name' => undef,
'contact_method_value' => 'example@example.com',
'contact_method_type_id' => '1',
'contact_method_id' => '24061',
'entity_id' => undef,
'contact_method_type_name' => 'Email'
}
],
'country_name' => undef,
'longitude' => undef,
'country_abbr_name' => undef,
'full_name' => 'NAME',
'networks' => [
{ 'network_name' => 'NET',
'network_id' => 'X'
}
],
'timezone_id' => undef,
'zip' => undef,
'timezone_name' => undef,
'title' => 'MAC/Network Specialist',
'first_name' => 'Terri'
},
{ 'contact_type_name' => 'Primary Technical Contact',
'street' => 'STREET',
'state_id' => undef,
'state_name' => undef,
'last_name' => 'NAME',
'entities' => [
{ 'entity_name' => 'NAME',
'entity_id' => '2679'
}
],
'state_abbr_name' => undef,
'city' => 'CITY',
'country_id' => undef,
'latitude' => undef,
'contact_id' => '7896',
'contact_type_id' => '1',
'roles' => [],
'contact_methods' => [
{ 'entity_name' => undef,
'contact_method_value' => 'example@example.com',
'contact_method_type_id' => '1',
'contact_method_id' => '16796',
'entity_id' => undef,
'contact_method_type_name' => 'Email'
},
{ 'entity_name' => undef,
'contact_method_value' => 'number',
'contact_method_type_id' => '2',
'contact_method_id' => '16797',
'entity_id' => undef,
'contact_method_type_name' => 'Office Phone'
}
],
'country_name' => undef,
'longitude' => undef,
'country_abbr_name' => undef,
'full_name' => 'NAME',
'networks' => [
{ 'network_name' => 'net',
'network_id' => '17'
}
],
'timezone_id' => undef,
'zip' => 'zip',
'timezone_name' => undef,
'title' => 'Infrastructure Manager',
'first_name' => 'name'
}
],
'offset' => '0'
},
...
当库存水平达到5或更低时，我希望在用户请求时从python更新库存水平。
我目前正在使用这段代码，我只是通过更新CSV中的一行来改编。虽然不行。第一行将作为34512340,0,95,95
12395675,3,95,92
56756777,70,95,25
90673412,2,95,93
写回文件，并删除文件的其余部分。
34512340,0,95,95以下是我在CSV文件中更改一行并运行的代码：
choice = input("\nTo update the stock levels of the above products, type 1. To cancel, enter anything else.")
if choice == '1':
with open('stockcontrol.csv',newline='') as f:
for line in f:
data = line.split(",")
productcode = int(data[0])
target = int(data[2])
stocklevel = int(data[1])
if stocklevel <= 5:
target = str(target)
import sys
import csv
data=[]
newval= target
newtlevel = "0"
f=open("stockcontrol.csv")
reader=csv.DictReader(f,fieldnames=['code','level', 'target', 'distancefromtarget'])
for line in reader:
line['level']= newval
line['distancefromtarget']= newtlevel
data.append('%s,%s,%s,%s'%(line['code'],line['level'],line['target'],line['distancefromtarget']))
f.close()
f=open("stockcontrol.csv","w")
f.write("\n".join(data))
f.close()
print("The stock levels were updated successfully")
else:
print("Goodbye")
我可以更改什么才能使代码生效？我基本上希望程序循环遍历CSV文件的每一行，如果库存水平（第2列）等于或小于5，则将库存水平更新为第3列中的目标数量，然后设置数量第4列为零。
谢谢，
答案 0 :(得分：1)
下面的代码读取每一行并检查第2列的值。如果它小于或等于5，则将column2的值更改为column3的值，将最后一列更改为0，否则将保留所有列不变。
import sys
import csv
data=[]
f=open("stockcontrol.csv")
reader=csv.DictReader(f,fieldnames=['code','level','target','distancefromtarget'])
for line in reader:
if int(line['level']) <= 5:
line['level']= line['target']
line['distancefromtarget']= 0
data.append("%s,%s,%s,%s"%(line['code'],line['level'],line['target'],line['distancefromtarget']))
f.close()
f=open("stockcontrol.csv","w")
f.write("\n".join(data))
f.close()
您的代码中出现问题：
您首先在不使用csv模块的情况下阅读该文件，并通过拆分该行来获取每列中的值。您再次使用DictReader模块的csv方法来阅读您已有的值。