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JavaScript: Extract a specific number of characters from a string

JavaScript String: Exercise-4 with Solution

Write a JavaScript function to extract a specified number of characters from a string.

Pictorial Presentation:

JavaScript: Extract a specific number of characters from a string

Test Data :
console.log(truncate_string("Robin Singh",4));
"Robi"

Sample Solution:-

HTML Code:

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Extract a specific number of characters from a string</title>
</head>
<body>
</body>
</html>

JavaScript Code:

truncate_string = function (str1, length) {
  
    if ((str1.constructor === String) && (length>0)) {
        return str1.slice(0, length);
    }
};
console.log(truncate_string("Robin Singh",4));

Sample Output:

Robi

Flowchart:

Flowchart: JavaScript- Extract a specific number of characters from a string

Live Demo:

See the Pen JavaScript Extract a specific number of characters from a string - string-ex-4 by w3resource (@w3resource) on CodePen.


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Next: Write a JavaScript function to convert a string in abbreviated form.

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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