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

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:

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

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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Previous: Write a JavaScript program to calculate the sum n + n/2 + n/4 + n/8 + .... where n is a positive integer and all divisions are integer.
Next: Write a JavaScript program to check whether a matrix is a diagonal matrix or not.

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JavaScript: Tips of the Day

Classes/function constructors

class Person {
  constructor() {
    this.name = 'Owen';
  }
}

Person = class AnotherPerson {
  constructor() {
    this.name = 'Eddie';
  }
};

const member = new Person();
console.log(member.name);

We can set classes equal to other classes/function constructors. In this case, we set Person equal to AnotherPerson. The name on this constructor is Eddie, so the name property on the new Person instance member is "Eddie".

Ref: https://bit.ly/3jFRBje