Replace space with underscore in Python

By Amandeep Singh

Strings are a fundamental information type in programming. In Python, we can regard strings as iterable characters and can play out various capabilities and procedures on them. Supplanting characters in a string is one such activity.

Ways to replace space with an underscore in Python

In this article, we will examine different techniques to supplant or replace space with an underscore in Python.

Method 1: Using the for loop

The for loop can emphasize over a string in Python. In each emphasis, we will contrast the character and whitespace. Assuming the match returns valid, we will supplant it with an underscore.

Python Code:

a = "Coding with Amandeep"
a1 = ""
for i in range(len(a)):
    if a[i] == ' ':
        a1 = a1 + '_'
    else:
        a1 = a1 + a[i]
print(a1)

Output:

Coding_with_Amandeep

Method 2: Using the replace() function

A substring from a string can be replaced using the replace() method. The number of instances we wish to replace within the function may also be specified. We will only supply these two characters within the method in order to replace any instances of space in a string with an underscore.

a = "Coding with Amandeep"
a = a.replace(' ', '_')
print(a)

Coding_with_Amandeep

import re
s = "Coding with Ammy"
a = re.sub('\s+', '_', s)
print(a)

Coding_with_Ammy

Method 4: Using the split() and join() function

Using a separator, the split() method will divide the text into a list. The space character is used as a separator by default.
The string will be divided into a list based on white space, and these components will be joined using the join() method with the underscore character serving as the separator.

Code:

s = "Coding with Ammy"
s = "_".join(s.split())
print(s)

Output:

Coding_with_Ammy

In this instructional exercise, we examined how to supplant a space with a highlight in a string. The replace() and re.sub() capabilities end up being the clearest strategies. The for-loop technique is an extensive and wasteful strategy. The join() and split() capabilities can be somewhat quick, however, this technique won’t work for a gathering of whitespace characters.