python中的成员运算符_Python中的成员运算符

我会带着你远行 2023-03-05 10:58 23阅读 0赞

python中的成员运算符

**Membership Operators** are the operators, which are used to check whether a value/variable exists in the sequence like string, list, tuples, sets, dictionary or not.

**成员运算**符是用于检查诸如字符串，列表，元组，集合，字典之类的序列中是否存在值/变量的运算符。

These operator returns either True or False, if a value/variable found in the list, its returns True otherwise it returns False.

这些运算符返回True或False ，如果在列表中找到一个值/变量，则返回True，否则返回False 。

## Python会员运算符 **(**Python Membership Operators**)** ##

<table> 
 <tbody> 
  <tr> 
   <th>Operator</th> 
   <th>Description</th> 
   <th>Example</th> 
  </tr> 
  <tr> 
   <td><span>in</span></td> 
   <td>It returns <span>True</span>, if a variable/value found in the sequence.</td> 
   <td><span>10 in list1</span></td> 
  </tr> 
  <tr> 
   <td><span>not in</span></td> 
   <td>It returns <span>True</span>, if a variable/value does not found in the sequence.</td> 
   <td><span>10 not in list1</span></td> 
  </tr> 
 </tbody> 
</table>

<table> 
 <tbody> 
  <tr> 
   <th> 操作员 </th> 
   <th> 描述 </th> 
   <th> 例 </th> 
  </tr> 
  <tr> 
   <td> 在 </td> 
   <td> 如果在序列中找到变量/值，则返回True 。 </td> 
   <td> 清单1中的10 </td> 
  </tr> 
  <tr> 
   <td> 不在 </td> 
   <td> 如果在序列中未找到变量/值，则返回True 。 </td> 
   <td> 10不在清单1中 </td> 
  </tr> 
 </tbody> 
</table>

**Example:**

**例：**

# Python example of "in" and "not in" Operators
    
    # declare a list and a string
    str1 = "Hello world"
    list1 = [10, 20, 30, 40, 50]
    
    # Check 'w' (capital exists in the str1 or not 
    if 'w' in str1:
    	print "Yes! w found in ", str1
    else:
    	print "No! w does not  found in " , str1
    
    # check 'X' (capital) exists in the str1 or not
    if 'X' not in str1:
    	print "yes! X does not exist in ", str1
    else:
    	print "No!  X exists in ", str1
    
    # check 30 exists in the list1 or not 
    if 30 in list1:
    	print "Yes! 30 found in ", list1
    else:
    	print "No! 30 does not found in ", list1
    
    # check 90 exists in the list1 or not
    if 90 not in list1:
    	print "Yes! 90 does not exist in ", list1
    else:
    	print "No! 90 exists in ", list1

**Output**

**输出量**

Yes! w found in  Hello world
        yes! X does not exist in  Hello world
        Yes! 30 found in  [10, 20, 30, 40, 50]
        Yes! 90 does not exist in  [10, 20, 30, 40, 50]

> 翻译自: [https://www.includehelp.com/python/membership-operators.aspx][https_www.includehelp.com_python_membership-operators.aspx]

python中的成员运算符

[https_www.includehelp.com_python_membership-operators.aspx]: https://www.includehelp.com/python/membership-operators.aspx