To make sure a string will display as expected, we can format the result with the format() method.
String format()
The format() method allows you to format selected parts of a string.
Sometimes there are parts of a text that you do not control, maybe they come from a database, or user input?
To control such values, add placeholders (curly brackets {}) in the text, and run the values through the format() method:
Example
Add a placeholder where you want to display the price:
price = 49
txt = “The price is {} dollars”
print(txt.format(price))
Output:
The price is 49 dollars
You can add parameters inside the curly brackets to specify how to convert the value:
Example
Format the price to be displayed as a number with two decimals:
txt = “The price is {:.2f} dollars”
Output:
The price is 49.00 dollars
Check out all formatting types in our String format() Reference.
Multiple Values
If you want to use more values, just add more values to the format() method:
print(txt.format(price, itemno, count))
And add more placeholders:
Example
quantity = 3
itemno = 567
price = 49
myorder = “I want {} pieces of item number {} for {:.2f} dollars.”
print(myorder.format(quantity, itemno, price))
Output:
I want 3 pieces of item number 567 for 49.00 dollars.
Index Numbers
You can use index numbers (a number inside the curly brackets {0}) to be sure the values are placed in the correct placeholders:
Example
quantity = 3
itemno = 567
price = 49
myorder = “I want {0} pieces of item number {1} for {2:.2f} dollars.”
print(myorder.format(quantity, itemno, price))
Output:
I want 3 pieces of item number 567 for 49.00 dollars.
Also, if you want to refer to the same value more than once, use the index number:
Example
age = 36
name = “John”
txt = “His name is {1}. {1} is {0} years old.”
print(txt.format(age, name))
Output:
His name is John. John is 36 years old.
Named Indexes
You can also use named indexes by entering a name inside the curly brackets {carname}, but then you must use names when you pass the parameter values txt.format(carname = "Ford"):
Example
myorder = “I have a {carname}, it is a {model}.”
print(myorder.format(carname = “Ford”, model = “Mustang”))
Output:
I have a Ford, it is a Mustang.