Check if string ends with desired character in JavaScript

In JavaScript, you can check if a string ends with a specific character using several built-in methods. The most common approaches are using endsWith(), charAt(), or bracket notation.

Understanding the Problem

We need to determine if a given string ends with a specific character. For example, checking if "Hello World!" ends with "!" should return true, while checking if "Hello World." ends with "!" should return false.

Using endsWith() Method (Recommended)

The endsWith() method is the most straightforward approach:

const str1 = "Hello, Tutorials Point!";
const str2 = "Hello, World.";
const desiredChar = "!";

console.log(str1.endsWith(desiredChar));  // true
console.log(str2.endsWith(desiredChar));  // false

// You can also check for multiple characters
console.log("JavaScript".endsWith("Script"));  // true
console.log("JavaScript".endsWith("Java"));    // false

true
false
true
false

Using charAt() Method

This method extracts the last character using charAt() and compares it:

function endsWithChar(str, character) {
    const lastChar = str.charAt(str.length - 1);
    return lastChar === character;
}

const inputStr = "Hello, Tutorials Point!";
const inputStr1 = "Hello, World.";
const desiredChar = "!";

console.log(endsWithChar(inputStr, desiredChar));   // true
console.log(endsWithChar(inputStr1, desiredChar));  // false

true
false

Using Bracket Notation

You can also access the last character using bracket notation:

function endsWithCharBracket(str, character) {
    return str[str.length - 1] === character;
}

const text = "Programming";
console.log(endsWithCharBracket(text, "g"));  // true
console.log(endsWithCharBracket(text, "m"));  // false

true
false

Comparison of Methods

Edge Cases

Handle empty strings and special cases:

function safeEndsWithChar(str, character) {
    if (!str || str.length === 0) {
        return false;
    }
    return str.endsWith(character);
}

console.log(safeEndsWithChar("", "!"));        // false
console.log(safeEndsWithChar("!", "!"));       // true
console.log(safeEndsWithChar("Hello!", "!"));  // true

false
true
true

Time Complexity

All methods have O(1) time complexity for single character checks, as they only access the last character of the string without iterating through the entire string.

Conclusion

Use endsWith() for modern applications as it's more readable and supports multi-character strings. For single characters in legacy environments, charAt() or bracket notation work effectively.