String

You can define a string using two single-quotes, two double-quotes, or two triple-quotes. For example, you can declare a string using s = "hello". Once you have a string, you can apply any of the methods listed in the functions portion.

Formatting Strings in Python

In Python2:

i = 1
s = "abc"
mystr1 = "{} {}".format(i, s)
mystr2 = "%d %s" % (i, s)
print(mystr1)               #1 abc
print(mystr2)               #1 abc

In Python3:

i = 1
s = "abc"
mystr1 = "{} {}".format(i, s)
mystr2 = f"{i} {s}"
print(mystr1)               #1 abc
print(mystr2)               #1 abc

There are multiple ways to format strings in Python2 and Python3. If you look at the above examples, you can see that "{} {}".format(i, s) works in both Python2 and Python3.

In Python2, you can use the % operator with strings to format strings through string interpolation. You should not use this function in Python3 because it is deprecated. The new way to do string interpolation in Python3 is through the use of the f operator.

Functions

  • str.capitalize()
  • str.center(width[, fillchar])
  • str.count(sub[, start[, end]])
  • str.endswith(suffix)
  • str.expandtabs([tabsize])
  • str.find(sub[, start[, end]])
  • str.format(*args, **kwargs)
  • str.index(sub[, start[, end]])
  • str.isalnum()
  • str.isalpha()
  • str.isdigit()
  • str.islower()
  • str.isnumeric()
  • str.isspace()
  • str.istitle()
  • str.isupper()
  • str.join(iterable)
  • str.ljust(width[, fillchar])
  • str.lower()
  • str.lstrip([chars])
  • str.partition(sep)
  • str.replace(old, new[, count])
  • str.rfind(sub[, start[, end]])
  • str.rindex(sub[, start[, end]])
  • str.rjust(width[, fillchar])
  • str.rpartition(sep)
  • str.rstrip([chars])
  • str.split(sep=None, maxsplit=-1)
  • str.splitlines([keepends])
  • str.startswith(prefix[, start[, end]])
  • str.strip([chars])
  • str.swapcase()
  • str.title()
  • str.upper()
  • str.zfill(width)

For information about how to use above functions, check out String Methods in Python's official documentation.

Example

a = "hello world"
print(a.capitalize())        # Hello world
print(a.upper())             # HELLO WORLD
print(a.find("world"))       # 6
print(a.split())             # ['hello', 'world']
print(a.isalnum())           # False

b = "hello {0} {1}"
print(b.format("Albert", "Einstein"))    # hello Albert Einstein

Reference