Getattr () function in Python

The getattr () function in Python returns the value of the property you want to find, if the object does not have this property the function will return the default value provided. How is the syntax of getattr () function, what parameters does it have, and how is it used? Invites you to read the track.

The getattr () function syntax in Python

 getattr(doituong, tenthuoctinh[, macdinh]) 

Parameters of getattr function ()

The getattr () function has 3 parameters:

1. Doituong: object you want to check.
2. tenthuoctinh: name of the attribute to search.
3. macdinh: Value returned if the property does not exist.

Note : getattr () function returns:

1. The value of the attribute if the object has an input attribute.
2. The default value if the object does not have a transfer attribute.
3. Exception AttributionError if no attributes are found and default values ​​are not specified.

Example 1: How does the getattr () function work?

 class Nhanvien: 
  tuoi = 23 
  ten = "QuachTinh" 
 
 nhanvien = Nhanvien() 
 print('So tuoi la:', getattr(nhanvien, "tuoi")) 
 print('So tuoi la:', nhanvien.tuoi) 

Run the program, the result is:

 So tuoi la: 23 
 So tuoi la: 23 

Example 2: Default value parameter

 class Nhanvien: 
  tuoi = 23 
  ten = "Adam" 
 
 nhanvien = Nhanvien() 
 
 # Khi truyền giá trị mặc định 
 # Viết bởi TipsMake.com 
 print('Gioi tinh nhan vien la:', getattr(nhanvien, 'gioitinh', 'Nam')) 
 
 # Khi không truyền giá trị mặc định 
 print('Gioi tinh nhan vien la:', getattr(nhanvien, 'gioitinh')) 

Running the program results in:

 Gioi tinh nhan vien la: Nam 
 AttributeError: 'Nhanvien' object has no attribute 'gioitinh' 

The attribute is not in the Nhanvien class , so when calling the getattr function with the default value of Male , the function will return 'Male', but if it does not pass this parameter as the code below, the program will generate an exception. AttributeError.

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