python不等于运算符的具体使用

Python not equal operator returns True if two variables are of same type and have different values, if the values are same then it returns False.

如果两个变量具有相同的类型并且具有不同的值 ，则Python不等于运算符将返回True ；如果值相同，则它将返回False 。

Python is dynamic and strongly typed language, so if the two variables have the same values but they are of different type, then not equal operator will return True.

Python是动态的强类型语言，因此，如果两个变量具有相同的值，但它们的类型不同，则不相等的运算符将返回True 。

Python不等于运算符 (Python not equal operators)

Python 2示例 (Python 2 Example)

Let's see some examples of not-equal operator in Python 2.7.

我们来看一些Python 2.7中不等于运算符的示例。

$ python2.7
Python 2.7.10 (default, Aug 17 2018, 19:45:58) 
[GCC 4.2.1 Compatible Apple LLVM 10.0.0 (clang-1000.0.42)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> 10 <> 20
True
>>> 10 <> 10
False
>>> 10 != 20
True
>>> 10 != 10
False
>>> '10' != 10
True
>>>

Python 3示例 (Python 3 Example)

Here is some examples with Python 3 console.

这是Python 3控制台的一些示例。

$ python3.7
Python 3.7.0 (v3.7.0:1bf9cc5093, Jun 26 2018, 23:26:24) 
[Clang 6.0 (clang-600.0.57)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> 10 <> 20
  File "<stdin>", line 1
    10 <> 20
        ^
SyntaxError: invalid syntax
>>> 10 != 20
True
>>> 10 != 10
False
>>> '10' != 10
True
>>>

We can use Python not equal operator withf-strings too if you are using Python 3.6 or higher version.

如果您使用的是Python 3.6或更高版本，我们也可以将Python不等于运算符与f字符串一起使用。

x = 10
y = 10
z = 20
 
print(f'x is not equal to y = {x!=y}')
 
flag = x != z
print(f'x is not equal to z = {flag}')
 
# python is strongly typed language
s = '10'
print(f'x is not equal to s = {x!=s}')

Output:

输出：

x is not equal to y = False
x is not equal to z = True
x is not equal to s = True

Python不等于自定义对象 (Python not equal with custom object)

When we use not equal operator, it calls __ne__(self, other) function. So we can define our custom implementation for an object and alter the natural output.

当我们使用不等于运算符时，它将调用__ne__(self, other)函数。 因此，我们可以为对象定义自定义实现并更改自然输出。

Let's say we have Data class with fields – id and record. When we are using the not-equal operator, we just want to compare it for record value. We can achieve this by implementing our own __ne__() function.

假设我们有带字段的Data类-id和record。 当我们使用不等于运算符时，我们只想比较它的记录值。 我们可以通过实现自己的__ne __（）函数来实现这一点。

class Data:
    id = 0
    record = ''
 
    def __init__(self, i, s):
        self.id = i
        self.record = s
 
    def __ne__(self, other):
        # return true if different types
        if type(other) != type(self):
            return True
        if self.record != other.record:
            return True
        else:
            return False
 
 
d1 = Data(1, 'Java')
d2 = Data(2, 'Java')
d3 = Data(3, 'Python')
 
print(d1 != d2)
print(d2 != d3)

Output:

输出：

False
True

Notice that d1 and d2 record values are same but “id” is different. If we remove __ne__() function, then the output will be like this:

请注意，d1和d2记录值相同，但“ id”不同。 如果删除__ne __（）函数，则输出将如下所示：

True
True

翻译自: https://www.journaldev.com/25101/python-not-equal-operator