经常遇到这样的场景，要根据不同字段的排序条件，输出符合要求的列表信息。经常我们把排序的逻辑写在 sql 语句中。如今，我有需要去验证数据的排序是否符合要求，所以要通过给你的数据，去验证它的排序逻辑。单个字段的排序还好，如果是多个字段，就会麻烦一些。晚上的思路比较活跃。果果和果妈已熟睡。代码如下，可以像 sql 一样的 order 语句，来对数组进行排序。
算是重复造轮子吧。
#!/usr/bin/python3
import pprint
def magic_sort(data=[{}], order="id desc",delimiter=";"):
'''
@param data list item is a dict
@param order string order like sql "id desc; status asc; field(id,2,-1,1)"
@return data list sorted data
@todo order by field
'''
orderArr = []
for item in order.lower().split(delimiter):
if "field" in item:
orderArr.append(item.strip()[6:-1].replace("","").split(',')) # ['id','2','-1','1']
else:
orderArr.append(item.strip().split())
orderArr.reverse() # 先排最后的字段，第一个字段，最后排序
size = len(data)
for o in orderArr:
key = int(o[0]) if o[0].isdigit() else o[0] # 如果 key 是数字字符，返回整数
if len(o) < 2:
ad = 'asc'
elif len(o) == 2:
ad = o[1]
else:
# order by field
data = sort_by_field(data,o)
continue
for i in range(size):
for j in range(size-i-1):
if (ad == 'desc' and data[j][key] < data[j+1][key]) or (ad == 'asc' and data[j][key] > data[j+1][key]):
data[j],data[j+1] = data[j+1],data[j]
return data
def sort_by_field(data,order):
field = order[0] # 字段
sort = order[1:] # 字段的排序 ['1','3','-1']
res = []
last = []
for o in sort:
for item in data:
if str(item[field]) == o:
res.append(item)
for item in data:
if str(item[field]) not in sort:
last.append(item)
return res+last
def _test_sort(params):
for param in params:
res = magic_sort(param['data'],param['order'])
myprint(res)
def myprint(param):
pp = pprint.PrettyPrinter(indent=4)
pp.pprint(param)
if __name__ == '__main__':
data = [{"id":1,"status":3,"age":12},
{"id":2,"status":1,"age":13},
{"id":2,"status":2,"age":14},
{"id":2,"status":3,"age":14},
{"id":4,"status":2,"age":15},
]
order = "id desc; field(status,1,3,2)"
#order = "field(status,1,3,2)"
params = [{"data":data,"order":order}]
ll = [[1,3,2,5],
[3,2,3,5],
[3,1,4,3],
[2,3,4,2],
[3,0,4,1],
[5,3,1,5],
]
llorder = "0 desc;1 asc;2 desc;3 desc"
params.append({"data":ll,"order":llorder})
_test_sort(params)