在python中，任何对象都可以判断其真假值：True，False

在if或while条件判断中，下面的情况值为False：

1.None

2.Flase

3.数值为0的情况，如：0,0.0,0j

4.所有空序列，如：'',(),[]

5.所有空mapping，如：{}

6.instances of user-defined classes,if the class defines a __bool__() or __len__() method,

when that method returns the integer zero or bool value False.

All other values are considered true — so objects of many types are always true.

在运算操作和内建函数返回Boolean结果0或者Flase表示false

1或True表示true

python中的Boolean运算如下：

# @param python中的Boolean运算和真假值
# @author 编程之家 jb51.cc|512Pic.com 

print('x or y -> if x is false,then y,else x ')
x,y = 2,0
print('{} or {} = {}'.format(x,y,x or y))
x1,y1 = 0,10
print('{} or {} = {}'.format(x1,y1,x1 or y1))
x2,y2 = 0,0
print('{} or {} = {}'.format(x2,y2,x2 or y2))
 
print('#' * 50)
print('x and y -> if x is false,then x,else y ')
print('{} and {} = {}'.format(x,x and y))
x1,10
print('{} and {} = {}'.format(x1,x1 and y1))
x2,0
print('{} and {} = {}'.format(x2,x2 and y2))
 
print('#' * 50)
print('not x -> if x is false,then True,else False ')
x = 2
print('not {} = {}'.format(x,not x))
x = 0
print('not {} = {}'.format(x,not x))

# End www.jb51.cc

运行结果：

>>>

x or y -> if x is false,else x

or 0 = 2

or 10 = 10

or 0 = 0

##################################################

x and y -> if x is false,else y

and 0 = 0

and 10 = 0

and 0 = 0

##################################################

not x -> if x is false,else False

not 2 = False

not 0 = True

>>>