d = {'a': [1], 'b': [1, 2], 'c': [], 'd':[]}
for i in d:
if not d[i]:
d.pop(i)
更改
In Python 2.x calling keys makes a copy of the key that you can iterate over while modifying the dict:
for i in d.keys():
Note that this doesn't work in Python 3.x because keys returns an iterator instead of a list.
Another way is to use list to force a copy of the keys to be made. This one also works in Python 3.x:
for i in list(d):
