# 定义测试用对象A，字典B
class A(object):
length = 10
B ={"length":10}
# 判断对象是否含有某种属性
# 推荐这种方式,更Pythonic
try:
x = A.lengt
except AttributeError:
print("does not have {}".format("lengt"))
# 这种low一点
if "leng" in dir(A):
print(A.length)
else:
print("does not have {}")
# 或者这种方式
try:
x = getattr(A,"length")
except AttributeError:
print("does not have {}".format("lengt"))
# 判断字典是否具有某个键：
try:
x = B[‘ssss‘]
except KeyError:
print("Not have")
# 或者
if x in x.keys():
do something
# 或者
if x.get(‘gridman‘):
do something
else
print("Not have")
# 获取属性的方式
# 对象
print(getattr(A,"length"))
print(A.length)
print(B.get("length","if not have return DefaultValue"))
print(B[‘length‘])【Python】字典或者对象类型中键或者属性的获取与存在性判断
原文：http://blog.51cto.com/l0vesql/2312725