replace() : search and replace a string inside a the main string in Python

Search for a string inside a main string and if found then replace it with another string

main_string.replace(search_string, replace_string, count)

search_string: Required , string to search within main string
replace_string: Required, string to replace if matching is found
count: ( Optional ) Number of times the replacement to happen. By default all matches will be replaced.

The original string is not changed.
This is case sensitive string search.
If the search string is not found inside main string, then main string is returned as output.

my_str='Welcome to PHP section of  plus2net'
output=my_str.replace('PHP','Python')
print(output)

Ouptut

Welcome to Python section of  plus2net

Replacing all occurrences of search string

my_str='Welcome to PHP section of  plus2net. PHP has many buit-in functions'
output=my_str.replace('PHP','Python')
print(output)

Output

Welcome to Python section of  plus2net. Python has many built-in functions

Using optional parameter count, we can replace only one occurrence.

my_str='Welcome to PHP section of  plus2net. PHP has many built-in functions'
output=my_str.replace('PHP','Python',1)
print(output)

Output

Welcome to Python section of  plus2net. PHP has many built-in functions

No matching is found, so input string is returned.

my_str='Welcome to PHP section of  plus2net'
output=my_str.replace('MySQL','Python')
print(output) # Nothing replaced as no matching found

Output is here

Welcome to PHP section of  plus2net

All String methods

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Subhendu Mohapatra

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