JavaScript: Check whether a given string represents a correct sentence or not

Last update on May 30 2022 10:07:54 (UTC/GMT +8 hours)

JavaScript Basic: Exercise-114 with Solution

Write a JavaScript program to check whether a given string represents a correct sentence or not. A string is considered correct sentence if it starts with the capital letter and ends with a full stop (.).

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title> Check whether a given string represents a correct sentence or not</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function is_correct_Sentence(input_str) {
    var first_char = input_str[0];
    var last_char = input_str[input_str.length - 1];
    return /[A-Z]/.test(first_char) && last_char == "."
}
console.log(is_correct_Sentence("This tool will help you write better English and efficiently corrects texts."));
console.log(is_correct_Sentence("This tool will help you write better English and efficiently corrects texts"));            
console.log(is_correct_Sentence("this tool will help you write better English and efficiently corrects texts."));

Sample Output:

true
false
false

Flowchart:

ES6 Version:

function is_correct_Sentence(input_str) {
    const first_char = input_str[0];
    const last_char = input_str[input_str.length - 1];
    return /[A-Z]/.test(first_char) && last_char == "."
}
console.log(is_correct_Sentence("This tool will help you write better English and efficiently corrects texts."));
console.log(is_correct_Sentence("This tool will help you write better English and efficiently corrects texts"));            
console.log(is_correct_Sentence("this tool will help you write better English and efficiently corrects texts."));

Live Demo:

See the Pen javascript-basic-exercise-114 by w3resource (@w3resource) on CodePen.

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Next: Write a JavaScript program to check whether a matrix is a diagonal matrix or not.

JavaScript: Tips of the Day

How to insert an item into an array at a specific index (JavaScript)?

What you want is the splice function on the native array object.

arr.splice(index, 0, item); will insert item into arr at the specified index (deleting 0 items first, that is, it's just an insert). In this example we will create an array and add an element to it into index 2:

var arr = []; arr[0] = "Jani"; arr[1] = "Hege"; arr[2] = "Stale"; arr[3] = "Kai Jim"; arr[4] = "Borge"; console.log(arr.join()); arr.splice(2, 0, "Lene"); console.log(arr.join());

Ref: https://bit.ly/2BXbp04