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我正在尝试仅打印 python 列表中的 dict 值。

car_object = {}
    cursor = self._db.execute('SELECT IDENT, MAKE, MODEL, DISPLACEMENT, POWER, LUXURY FROM CARS')
    for row in cursor:
       objectname = 'Car_Object_'+str(row['IDENT'])
       # print (objectname)
       car_object[objectname] = Cars(ident = row['IDENT'], make = row['MAKE'], model = row['MODEL'], disp = row['DISPLACEMENT'], power = row['POWER'], luxury = row['LUXURY'])
       print(objectname, car_object[objectname])
        #print(row['IDENT'], row['MAKE'], row['MODEL'], row['DISPLACEMENT'], row['POWER'], row['LUXURY'])

       yield dict(row)

所以它正在打印:

Car_Object_meA160 {'power': 55, 'ident': 'meA160', 'model': 'A160 CDI', 'disp': 1.7, 'make': 'mercedes', 'luxury': 'N'}
Car_Object_meA190 {'power': 92, 'ident': 'meA190', 'model': 'A190', 'disp': 1.7, 'make': 'mercedes', 'luxury': 'Y'}
Car_Object_meA210 {'power': 103, 'ident': 'meA210', 'model': 'A210 EVO', 'disp': 1.7, 'make': 'mercedes', 'luxury': 'Y'}

...等等我希望能够像这样打印它:

                      IDENT         MAKE         MODEL        DISP       POWER     LUX
Car_Object_meA160     meA160       mercedes      A160 CDI     1.7          55      N
Car_Object_meA190     meA190       mercedes      A190         1.7          92      Y
Car_Object_meA210     meA210       mercedes      A210 EVO     1.7          103     Y

所以我希望能够只打印值....标题以某种方式排序。是否有可能做到这一点?谢谢。

4

4 回答 4

1

棘手的部分是对齐几个表格条目和表格标题。为此,我们首先必须找出每列中最长的条目有多长。padthen 可用于向给定字符串添加多个填充空格。

fields = ["ident", "make", "model", "disp", "power", "luxury"]
max_len = {"name": max(map(len, car_objects)) + 1}
for f in fields:
    max_len[f] = max(map(len, [f] + [str(car[f]) for car in car_objects.values()]))
pad = lambda s, f: str(s).ljust(max_len[f])

car_objects现在,我们可以使用pad上面定义的函数打印标题和几个条目。

print pad("", "name") + " ".join(pad(f.upper(), f) for f in fields)
for name, car in car_objects.items():
    print pad(name, "name") + " ".join(pad(car[f], f) for f in fields)

假设 的元素car_objects是 Python 字典,这应该可以工作。如果没有,请尝试在上面的代码中car[f]替换为。getattr(c, f)

更新:当然,只有在实际打印之前知道所有行时,才能完美对齐表格的列。如果您必须在仍然从数据库中读取条目的同时打印它们,则必须“猜测”填充字符串的空格数,以便它们在表格中很好地对齐。这使一切变得更加简单。只需将此行放在您的for循环之前以打印表头:

print (" " * 20) + " ".join(f.upper().ljust(10) for f in fields)

而这一行在你的循环中,在之前yield

print name.ljust(20) + " ".join(str(getattr(car, f)).ljust(10) for f in fields)

str.ljust(n)是一个标准的字符串函数,它返回在字符总宽度内左对齐的字符串n。右对齐和居中对齐也有类似的功能:rjustcenter. 而且由于您的汽车似乎是某个类的实例,因此您可以使用内置函数getattr(<object>, <attribute name>)来检索汽车的各个属性(类似于您的getVariable方法)。

有关字符串格式的更多信息,请查看此Python 文档页面

于 2013-03-01T15:38:33.867 回答
0

试试这个:

#print your header labels first                                                                                                                       
d = {'power': 55, 'ident': 'meA160', 'model': 'A160 CDI', 'disp': 1.7, 'make': 'mercedes', 'luxury': 'N'}
# this is for each car                                                                                                                                
headers = ['ident', 'make', 'model', 'disp', 'power', 'luxury'] # change this order if you   want different order                                       
values = [d[h] for h in headers]
print("{0:12}{1:12}{2:12}{3:12}{4:12}{5:12}".format(values[0], values[1], values[2], values[3], values[4], values[5]))
于 2013-03-01T14:55:04.137 回答
0

尝试以下操作...我使用字典对其进行了测试,因此我可以访问您拥有的属性为car_object[obj][key.lower()]. 我不能不看你的 Cars 课程,但你可能应该用类似的东西替换它car_obj[obj].__getattribute__(key.lower())

car_object = {}
car_object['Car_Object_meA160'] = {'power': 55, 'ident': 'meA160', 'model': 'A160 CDI', 'disp': 1.7, 'make': 'mercedes', 'luxury': 'N'}
car_object['Car_Object_meA190'] = {'power': 92, 'ident': 'meA190', 'model': 'A190', 'disp': 1.7, 'make': 'mercedes', 'luxury': 'Y'}
car_object['Car_Object_meA210'] = {'power': 103, 'ident': 'meA210', 'model': 'A210 EVO', 'disp': 1.7, 'make': 'mercedes', 'luxury': 'Y'}

keys = ['IDENT', 'MAKE', 'MODEL', 'DISP', 'POWER', 'LUXURY']
fmt ='{:>10}' * (len(keys) + 1)
print ' '*len('Car_Object_meA160'), fmt.format('', *keys)

for obj in car_object:
    print obj, fmt.format('', *([car_object[obj][key.lower()] for key in keys]))
于 2013-03-01T15:06:53.620 回答
-1

是的。这是一个快速功能,它可以获取列表并打印出您想要的内容。

def output(cars):
    print "          IDENT        MAKE        MODEL        DISP        POWER"
    for i in cars:
        print type(i),"    ",i[ident],"   ",i[make],"   ",i[model],"   ",i[disp],"   ",i[power]

它应该打印出您放置的尽可能多的汽车。虽然我对间距并不积极。

于 2013-03-01T15:04:56.227 回答