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JavaScript: Create a string using the middle three characters of a given string of odd length

JavaScript Basic: Exercise-63 with Solution

Write a JavaScript program to create a string using the middle three characters of a given string of odd length. The string length must be greater or equal to three.

Pictorial Presentation:

JavaScript: Create a string using the middle three characters of a given string of odd length

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JavaScript program to create a string using the middle three characters of a given string of odd length. The string length must be 3.</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function middle_three(str) {
   if (str.length % 2!= 0) {
   
    mid = (str.length + 1)/2;
    return str.slice(mid - 2, mid + 1);
    }
  return str;
}
console.log(middle_three('abcdefg'));
console.log(middle_three('HTML5'));
console.log(middle_three('Python'));
console.log(middle_three('PHP'));
console.log(middle_three('Exercises'));

Sample Output:

cde
TML
Python
PHP
rci

Flowchart:

Flowchart: JavaScript - Create a string using the middle three characters of a given string of odd length

ES6 Version:

function middle_three(str) {
   if (str.length % 2!= 0) {
   
    mid = (str.length + 1)/2;
    return str.slice(mid - 2, mid + 1);
    }
  return str;
}
console.log(middle_three('abcdefg'));
console.log(middle_three('HTML5'));
console.log(middle_three('Python'));
console.log(middle_three('PHP'));
console.log(middle_three('Exercises'));

Live Demo:

See the Pen JavaScript - Create a string using the middle three characters of a given string of odd length - basic-ex-63 by w3resource (@w3resource) on CodePen.


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JavaScript: Tips of the Day

Converts a string to title case

Example:

const toTitleCase = str =>
  str
    .match(/[A-Z]{2,}(?=[A-Z][a-z]+[0-9]*|\b)|[A-Z]?[a-z]+[0-9]*|[A-Z]|[0-9]+/g)
    .map(x => x.charAt(0).toUpperCase() + x.slice(1))
    .join(' ');
console.log(toTitleCase('some_database_field_name')); // 'Some Database Field Name'
console.log(toTitleCase('Some label that needs to be title-cased')); // 'Some Label That Needs To Be Title Cased'
console.log(toTitleCase('some-package-name')); // 'Some Package Name'
console.log(toTitleCase('some-mixed_string with spaces_underscores-and-hyphens')); // 'Some Mixed String With Spaces Underscores And Hyphens' 

Output:

"Some Database Field Name"
"Some Label That Needs To Be Title Cased"
"Some Package Name"
"Some Mixed String With Spaces Underscores And Hyphens"