Python - Format Strings

In Python, you can format strings to include variables or values using the format() method. This allows you to create dynamic strings with placeholders that are replaced by specific values at runtime.

Basic String Formatting

To use the format() method, define a string with placeholder braces {} where you want to insert values, and then call format() on that string, passing the values as arguments.

Example

age = 36
txt = "My name is John, and I am {}"
print(txt.format(age))

In this example, {} serves as a placeholder for the age variable. The format() method replaces the placeholder with the value of age.

Multiple Placeholders

You can use multiple placeholders within the same string and pass multiple values to the format() method.

Example

quantity = 3
itemno = 567
price = 49.95
myorder = "I want {} pieces of item {} for {} dollars."
print(myorder.format(quantity, itemno, price))

In this example, three placeholders are used to format the myorder string, and three values are passed to format() to replace these placeholders.

Index Numbers

If you want to ensure that the arguments are placed in the correct placeholders, you can use index numbers within the placeholders.

Example

quantity = 3
itemno = 567
price = 49.95
myorder = "I want to pay {2} dollars for {0} pieces of item {1}."
print(myorder.format(quantity, itemno, price))

By specifying index numbers within the placeholders (e.g., {2}), you can control the order of argument insertion.

String formatting with format() is a powerful way to create dynamic and flexible strings that include variables, numbers, and other values.