Python中的delattr()和del()
这两个函数用于从类中删除属性。在delattr()允许属性的dynamoc缺失，而del()在删除属性更高效的明确。
使用delattr()
Syntax: delattr(object_name, attribute_name) Where object name is the name of the object, instantiated form the class. Attribute_name is the name of the attribute to be deleted.
示例
在下面的示例中，我们考虑一个名为custclass的类。它具有客户的ID作为其属性。接下来，我们将该类实例化为一个名为customer的对象，并打印其属性。
class custclass: custid1 = 0 custid2 = 1 custid3 = 2 customer=custclass() print(customer.custid1) print(customer.custid2) print(customer.custid3)
输出结果
运行上面的代码给我们以下结果-
0 1 2
示例
在下一步中，我们通过应用delattr()方法再次运行程序。这次，当我们要打印id3时，由于该属性已从类中删除，因此会出现错误。
class custclass: custid1 = 0 custid2 = 1 custid3 = 2 customer=custclass() print(customer.custid1) print(customer.custid2) delattr(custclass,'custid3') print(customer.custid3)
输出结果
运行上面的代码给我们以下结果-
0 Traceback (most recent call last): 1 File "xxx.py", line 13, in print(customer.custid3) AttributeError: 'custclass' object has no attribute 'custid3'
使用del()
Syntax: del(object_name.attribute_name) Where object name is the name of the object, instantiated form the class. Attribute_name is the name of the attribute to be deleted.
示例
我们用del()函数重复上面的例子。请注意，语法与delattr()
class custclass: custid1 = 0 custid2 = 1 custid3 = 2 customer=custclass() print(customer.custid1) print(customer.custid2) del(custclass.custid3) print(customer.custid3)
输出结果
运行上面的代码给我们以下结果-
0 1 Traceback (most recent call last): File "xxx.py", line 13, in print(customer.custid3) AttributeError: 'custclass' object has no attribute 'custid3'