Replace() function is one of the methods to remove the leading and trailing comma from a string using JavaScript. In this article we will talk about it with the explanation and examples below. Let’s check it out!
Trailing Comma
A trailing comma leaves a comma after the last element at the end of a list (it can be an element in an Array literal), a property in an Object literal, or a function parameter.
And if you use an old browser that only supports ECMAScript 3 or earlier (IE8), the program will give an error when leaving extra commas at the end of the params.
Trailing commas are only helpful with lists on multiple lines, so you don’t need to leave any commas when the list is short on the same line.
With function parameter lists, trailing commas were only accepted in ES2017. If the JS engine does not yet support it, and when run directly, it will cause a syntax error. So it is safer if your code is compiled through Babel and preset-env.
Therefore, you should still avoid using trailing commas in function parameters. When writing functions with too long parameter lists, you should use object literals to collect the list of parameters.
Remove the leading and trailing comma from a string using JavaScript
Using replace() method
The replace() method is used to replace all old characters or strings with new characters or strings.
In this way, we will use the replace method of the string to be able to search and replace the leading and Trailing Comma. Let’s see the code below and watch the input and output strings change.
Code:
var string = ",John, Kevin, Nick,";
var result = string.replace(/(^,)|(,$)/g, "");
console.log(result);Output:
John, Kevin, NickThen we replace them with the empty string and we can get the result of this topic.
Using split() & trim() & join() method
This would be a way to use more string-handling methods, but it seems more manageable for the coder to understand. Firstly, we will use the split() method to split the string into an array of separate words separated by “,” then use the trim() method to remove the spaces before and after the substring.
Code:
var string = ",John, Kevin, Nick,";
var result= string.split(',').map(e => e.trim()).filter(e => e).join(', ')
console.log(result);Output:
John, Kevin, NickFinally, we use the join() method to join the substrings in the array, and we get the new string to remove the leading and trailing comma. I hope these methods are helpful to you.
Summary
To summarize, this article shows you two ways to remove the leading and trailing comma from a string using JavaScript. You can use replace() method or combination of function: split() & trim() & join() to get the same result. Good luck for you!
Maybe you are interested:
- Remove leading and trailing Spaces from a String using JavaScript
- How To Remove the Last 3 Characters from a String using JavaScript
- Replace all Spaces in a String in JavaScript
- Remove all Whitespace from a String in JavaScript
Hi, my name’s Nathaniel Kirk. I’m interested in learning and sharing knowledge about programming languages. My strengths are C, C++, Python, HTML, CSS, Javascript, and Reactjs. If you have difficulty with them, don’t worry. I’m here to support you.
Name of the university: PTIT
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Programming Languages: C, C++, Python, HTML, CSS, Javascript, Reactjs