Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Showing content from https://www.tutorialspoint.com/python/python_string_format_map_method.htm below:

Python String format_map() Method

The Python String format_map() method is used to is used to perform string formatting with the help of a mapping object, such as a dictionary.

It is similar to the format() method but instead of passing arguments directly, it takes a single mapping object as its argument. This mapping object contains "key-value" pairs where the "keys" correspond to the placeholders in the string, and the "values" represent the replacements for those placeholders.

Following is the basic syntax of the Python String format_map() method −

string.format_map(mapping)

This method accepts a mapping object (such as a dictionary) that contains key-value pairs as a parameter.

The method returns a formatted string with the placeholders replaced by their corresponding values from the mapping. It does not modify the original string.

In the following example, we are formatting a string using a dictionary person with keys 'name' and 'age'. The format_map() method replaces placeholders "{name}" and "{age}" with the corresponding values from the dictionary −

person = {'name': 'Alice', 'age': 25}
result = "Name: {name}, Age: {age}".format_map(person)
print(result)  

The output obtained is as follows −

Name: Alice, Age: 25

Here, we access nested values in the dictionary "student". The format_map() method replaces placeholders "{details[name]}" and "{details[age]}" with the corresponding nested values −

student = {'details': {'name': 'Bob', 'age': 20}}
result = "Name: {details[name]}, Age: {details[age]}".format_map(student)
print(result)  

Following is the output of the above code −

Name: Bob, Age: 20

In this example, we format a string using attributes of an object "person" dynamically. The vars() function converts the object's attributes into a dictionary, which is then used by format_map() method to replace placeholders −

class Person:
    pass

person = Person()
person.name = 'John'
person.age = 30

result = "Name: {name}, Age: {age}".format_map(vars(person))
print(result)  

The result produced is as shown below −

Name: John, Age: 30

In here, we define a custom dictionary class "CustomDict" where missing keys are handled by the __missing__() method. If a key is missing in the dictionary data, it returns a custom string instead of raising a KeyError −

class CustomDict(dict):
    def __missing__(self, key):
        return f'Unknown: {key}'

data = CustomDict({'name': 'Alice'})
result = "Name: {name}, Age: {age}".format_map(data)
print(result)  

We get the output as shown below −

Name: Alice, Age: Unknown: age

python_string_methods.htm

RetroSearch is an open source project built by @garambo | Open a GitHub Issue

Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo

HTML: 3.2 | Encoding: UTF-8 | Version: 0.7.4