This article discusses replacing all spaces in a javascript string with underscore using different methods and illustrations.
Table of Contents:-
- Javascript string replace all spaces with underscores using replace() method
- ‘Javascript string replace all spaces with underscores using replaceAll() method
- Javascript string replace all spaces with underscores using split and join
- Javascript string replace all spaces with underscores using custom method
Javascript string replace all spaces with underscores using replace() method
The javascript replace() method finds a pattern and replaces some or all of its occurrences with a replacement(character/string). The pattern can be a character or a string, or regExp.
Syntax:-
replace(regexp, newSubstring) replace(stringToBeReplaced, newSubstring)
Example:-
Replace all occurrences of ” ” space with “_” underscore from the string “Javascript is the most popular language”
let dummyString = "Javascript is the most popular language";
newDummyString = dummyString.replace(/ /g, "_");
console.log("Old String is: "+ dummyString);
console.log("New String is: "+ newDummyString);
OR
let dummyString = "Javascript is the most popular language";
newDummyString = dummyString.replace(/\s+/g,"_");
console.log("Old String is: "+ dummyString);
console.log("New String is: "+ newDummyString); */
Output:-
Old String is: Javascript is the most popular language New String is: Javascript_is_the_most_popular_language
Javascript string replace all spaces with underscores using replaceAll() method
The replaceAll() method in javascript returns a new string with all matches of a pattern replaced by a replacement(character/string).
Syntax:-
replaceAll(regexp, newSubstring) replaceAll(stringToBeReplaced, newSubstring)
Example:-
Replace all occurrences of ” ” spaces with “_” underscore from the string “Javascript is the most popular language”
let dummyString = "Javascript is the most popular language";
newDummyString = dummyString.replaceAll(" ", "_");
console.log("Old String is: "+ dummyString);
console.log("New String is: "+ newDummyString);
Output:-
Old String is: Javascript is the most popular language New String is: Javascript_is_the_most_popular_language
Javascript string replace all spaces with underscores using split and join
This section will replace all ” ” spaces in the javascript string by splitting and joining an array. The solution is to split the original string by ” ” space and then replace it with “_” underscore. Then, finally, joining back into one string.
Syntax:-
newString = originalString.split(" ").join("_")
Example:-
Replace all occurrences of ” ” spaces with “_” underscore from the string “Javascript is the most popular language”
let dummyString = "Javascript is the most popular language";
newDummyString = dummyString.split(' ').join('_')
console.log("Old String is: "+ dummyString);
console.log("New String is: "+ newDummyString);
Output:-
Old String is: Javascript is the most popular language New String is: Javascript_is_the_most_popular_language
Javascript string replace all spaces with underscores using substring() and indexOf() methods
This section will replace all occurrences of ” ” spaces in the javascript string with the “_” underscore. Observe the below code:
Example:-
Replace all occurrences of ” ” spaces with “_” underscore from the string “Javascript is the most popular language”
let dummyString = "Javascript is the most popular language";
let i=-1;
let findToken = ' '
let newToken ='_'
while (( i=dummyString.indexOf(findToken,i>=0? i=newToken.length : 0 )) !== -1
)
{ dummyString= dummyString.substring(0,i) + newToken + dummyString.substring(i+findToken.length)}
console.log(dummyString)
Output:-
Javascript_is_the_most_popular_language
Explanation:-
- Finding the indexOf of  ” ” space.
- Identify the ” ” space to be replaced based on the index and then replace it with “_” underscore.
- Finally, concatenating the substrings to one string.
Read More:
- Javascript: Replace special characters in a string
- Javascript: Replace all occurrences of string (4 ways)
- Javascript check if string contains substring
- Javascript: Check if string is empty (6 ways)
We hope this article helped you replace all occurrences ” ” spaces in a javascript string with an “_” underscore. Good Luck !!!