JavaScript: Generates a string id (specified length) of random characters

JavaScript Function: Exercise-20 with Solution

Generate Random String ID

Write a JavaScript function that generates a string ID (specified length) of random characters.

Sample character list : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"

Sample Solution-1:

JavaScript Code:

// Define a function named makeid that generates a random string of specified length (l)
function makeid(l) {
  // Initialize an empty string named text to store the generated random string
  var text = "";
  
  // Define a character list containing uppercase letters, lowercase letters, and digits
  var char_list = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

  // Iterate l times to generate each character in the random string
  for (var i = 0; i < l; i++) {
    // Append a randomly selected character from char_list to the text string
    text += char_list.charAt(Math.floor(Math.random() * char_list.length));
  }

  // Return the generated random string
  return text;
}

// Log the result of calling makeid with the parameter 8 to the console
console.log(makeid(8)); 

Output:

4SGqCfrz

Flowchart:

Live Demo:

See the Pen JavaScript - Generates a string id (specified length) of random characters-function-ex- 20 by w3resource (@w3resource) on CodePen.

Sample Solution-2:

JavaScript Code:

// Function to generate a random string ID
function generateRandomString(length) {
    const characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    let result = '';

    for (let i = 0; i < length; i++) {
        // Randomly select a character from the characters string
        const randomIndex = Math.floor(Math.random() * characters.length);
        result += characters.charAt(randomIndex);
    }

    return result;
}

// Example usage:
const idLength = 10;
const randomID = generateRandomString(idLength);

// Log the generated ID to the console
console.log(randomID);

Output:

4SGqCfrz

Flowchart:

For more Practice: Solve these Related Problems:

• Write a JavaScript function that generates a random string ID of a specified length using Math.random.
• Write a JavaScript function that creates a random alphanumeric string ID by shuffling an array of characters.
• Write a JavaScript function that generates a random string ID ensuring uniqueness without using external libraries.
• Write a JavaScript function that generates a random string ID and incorporates special characters along with alphanumeric characters.

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