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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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Previous: Write a JavaScript function to split a string and convert it into an array of words.
Next: Write a JavaScript function to convert a string in abbreviated form.

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JavaScript: Tips of the Day

JavaScript: Shorten your "if" statements

Now this is a tricky one.
Shortening your0 "if" statements can be a great way to simplify your code.
However, if you need to write more complicated statements, you should definitely go for the first option.

// Instead of using this                                      
if (iAmHungry) {
   bakeAnEgg()
}
// You can use this
if (iAmHungry) bakeAnEgg()
// Or this
iAmHungry? bakeAnEgg() : 0

Remember, readability & ease-of-use are more important than a couple less lines of code.

Ref: https://bit.ly/2LBj213