4 Simple Ways in JavaScript to remove last character from string

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Removing the last character from a string is a common operation in string manipulation. While seemingly simple, JavaScript initially did not provide a direct string function to remove or truncate the last character.

However, over the years with more modern syntax and methods added, we now have cleaner options to achieve this.

In this quick article, We will briefly review a few different ways to remove the last character from string in JavaScript with examples using different techniques ranging from substring to regular expressions.

Remove Last Character from String in JavaScript

Below are some ways with the help of which you can remove the last character from string in JavaScript, so let’s dive into the methods:

1. Using Substring & Slice

JavaScript offers the .substring() method to us, that can help us in getting a substring portion of the given string. For example, substring of a string – “Hello” can be “ello”, “Hell”, “He” and many more. So to remove last character from string in JavaScript we will make use of the .substring() method. Here’s a brief overview of what the .substring() method looks like:

str.substring(startIndex, endIndex);

It takes two arguments, 1st one if startIndex which will be the starting index of our subtring, and an endIndex which will be the end index of our subtring.

One thing to note here is that, it will not consider the endIndex element to be included in the substring.

Here’s an example of using .substring() method to remove last character from string in JavaScript.

JavaScript

let msg = "Hello World";

trimmed_msg = msg.substring(0, msg.length - 1);

console.log(trimmed_msg); // Output - "Hello Worl"

This code above runs the .substring() method on our msg string which contains “Hello World” as a message and in the .substring() method itself, it takes 2 arguments which are 0 and msg.length – 1, which means that we need a substring from the 0th index to last-index of our string ( well, of course it will further exclude the last-index ).

Alternatively, you can also use the .slice() method of JavaScript to remove last character from string. It also takes 2 indexes as an argument and will return us with the substring required.

Here’s a piece of code in JavaScript that uses .slice() method:

JavaScript

let msg = "Hello World";

trimmed_msg = msg.slice(0, -1); 

console.log(trimmed_msg); // Output - "Hello Worl"

It took 2 arguments 0 and -1 as the starting and ending index of our substring. -1 here is used to depicted the last-index in the string.

2. Trim with Replace

The JavaScript replace string method is an extremely versatile way to find and replace substrings using regular expressions. While replace is often used for general search and replace operations, we can leverage regex matching groups to precisely target just the last character as well.

For example, consider we have the string:

JavaScript

let str = "Hello World";

We want to remove the last letter ‘d’ to get “Hello Worl”.

A regex pattern that would match this is:

/.$/

Here:

  • . matches any single character
  • $ denotes the boundary matching the end of the string

So together this regex will match ONLY the last character in the string.

We can use this pattern with string replace to replace the last character with an empty string, thereby removing it:

JavaScript

let msg = “Hello World”; 

trimmed_msg = msg.replace(/.$/, “”);

console.log(trimmed_msg); // "Hello Worl"

3. Split and Join Back

The JavaScript split and join methods provide an alternative approach to removing the last character from a string by leveraging arrays.

We first split this string into an array of characters by splitting on an empty string, this separates the string “Hello World” into the array. This strArray contains all characters individually.

We can now leverage the fact that the pop() method removes and returns the last element from an array. So we can remove the last letter ‘d’ using .pop(), this pops off ‘d’. Finally, we recombine the array of characters into a string using .join().

JavaScript

let msg = “Hello World”

let strArray = msg.split(“”); // ['H', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l', 'd']

strArray.pop();  // Removes "d" from the end : ['H', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l']

msg = strArray.join(“”);

console.log(msg); // "Hello Worl"

This splits the string on each character into an array, pops removes the last entry, then join concatenates entries back into a string.

4. Shorthand with Regex Matching

As we want “Hello Worl” without the ‘d’. A regular expression can match this in one go:

str = str.match(/^.*(..)$/)[1];

Let’s break this down –

  • ^ – Matches the start of the input
  • .* – Matches any characters greedily
  • (..) – Capturing group that matches the last 2 characters
  • $ – End of input boundary

So together ^.* grabs all the initial characters, (..) captures the last 2 characters separately, and $ ensures we only go until the end.

The key is match() here returns an array with two entries – the full match, and our captured group of last 2 characters.

By taking match group index [1], we isolate just “ld”.

JavaScript

let msg = “Hello World”;

trimmed_msg = msg.match(/^.*(..)$/)[1]; 

console.log(trimmed_msg); // "Hello Worl"

While cryptic, this leverages the fact you can extract sub-matches using regex groups along with matching beginning and end of input to trim precisely.

The regex could be extended more flexibly to cut off longer tail ends as well with more generic quantifiers. But for specifically the last character, this one-liner works cleanly!

StackOverflow Question – https://stackoverflow.com/questions/952924/how-do-i-chop-slice-trim-off-last-character-in-string-using-javascript

Conclusion

To Sum up, we discussed the approaches to remove last character from string in javascript, these includes using methods such as .substring(), .slice() and .replace(). Moreover, we did something more than that we also used the Split and Join back procedure in order to remove the last character from string and it gave us the same output. I hope you try them on your own and see if you’re able to implement them wherever necessary.

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