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JavaScript: Truncate a string if it is longer than the specified number of characters

JavaScript String: Exercise-16 with Solution

Write a JavaScript function to truncate a string if it is longer than the specified number of characters. Truncated strings will end with a translatable ellipsis sequence ("…") (by default) or specified characters.

Test Data:
console.log(text_truncate('We are doing JS string exercises.'))
console.log(text_truncate('We are doing JS string exercises.',19))
console.log(text_truncate('We are doing JS string exercises.',15,'!!'))
"We are doing JS string exercises."
"We are doing JS ..."
"We are doing !!"

Sample Solution:-

HTML Code:

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>JS truncates a string</title>
</head>
<body>
</body>
</html>

JavaScript Code:

text_truncate = function(str, length, ending) {
    if (length == null) {
      length = 100;
    }
    if (ending == null) {
      ending = '...';
    }
    if (str.length > length) {
      return str.substring(0, length - ending.length) + ending;
    } else {
      return str;
    }
  };
console.log(text_truncate('We are doing JS string exercises.'))
console.log(text_truncate('We are doing JS string exercises.',19))
console.log(text_truncate('We are doing JS string exercises.',15,'!!'))

Sample Output:

We are doing JS string exercises.
We are doing JS ...
We are doing !!

Flowchart:

Flowchart: JavaScript- Truncate a string if it is longer than the specified number of characters

Live Demo:

See the Pen JavaScript Truncate a string if it is longer than the specified number of characters - string-ex-16 by w3resource (@w3resource) on CodePen.


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Previous: Write a JavaScript function to humanized number (Formats a number to a human-readable string.) with the correct suffix such as 1st, 2nd, 3rd or 4th.
Next: Write a JavaScript function to chop a string into chunks of a given length.

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JavaScript: Tips of the Day

JavaScript: Implicit type coercion

function sum(a, b) {
  return a + b;
}

sum(1, '2');

JavaScript is a dynamically typed language: we don't specify what types certain variables are. Values can automatically be converted into another type without you knowing, which is called implicit type coercion. Coercion is converting from one type into another.

In this example, JavaScript converts the number 1 into a string, in order for the function to make sense and return a value. During the addition of a numeric type (1) and a string type ('2'), the number is treated as a string. We can concatenate strings like "Hello" + "World", so what's happening here is "1" + "2" which returns "12".

Ref: https://bit.ly/323Y0P6