Python case-specific string methods are especially useful in instances when you need to compare two input values. You might also use them for other types of data validation or tasks related to content publishing.
1. The capitalize() Method
The capitalize() method converts the first character in a string to uppercase and returns an updated copy of the string.
The code above prints the following output in your Python IDE console:
The capitalize() method only changes the case of the first character if it is a letter of the alphabet (not integers).
The capitalize() method only changes the case of the first character if it is not already in uppercase.
The capitalize() method also ensures that every letter that is not in the first position converts to lower case in the new string.
2. The lower() and upper() Methods
These two methods help you convert strings to all lowercase or uppercase equivalents. They save you from having to manually convert string case yourself.
The lower() method takes no arguments and returns a new string. It converts each character into its lowercase equivalent:
The upper() method does the exact opposite of the lower() method. It converts all the lowercase characters in a string to uppercase. If there are no lowercase characters in the string this method returns an identical copy of the original string.
3. The casefold() Method
The casefold() method returns a copy of a string, where it converts each character to lowercase. However, it’s also a little more powerful than lower(). This function handles Unicode characters in such a way that lets you accurately compare strings containing them.
4. The islower() and isupper() Methods
The islower() and the isupper() string methods take no arguments. Each returns a boolean value. The islower() method returns true if every character in a string is lowercase, otherwise it returns false.
The isupper() method returns true if all the characters in a string are uppercase, otherwise it returns false.
5. The istitle() Method
The istitle() method returns true if all the words in a string begin with an uppercase letter, otherwise it returns false. This method takes no arguments.
6. The swapcase() Method
The swapcase() method takes no arguments and returns a new string with inverted case.
The Value of Python String Methods
String methods make life much easier for you as a Python programmer. For example, you can create a program that traverses through a string and converts all its letters to lowercase. However, given the existence of Python string methods, such as casefold(), that task would be much like reinventing the wheel.
Python string methods allow you to accomplish more with less effort.
