Step 1: Basic random string generator

We start by creating a simple function that will generate a random string. We will limit our characters to A-Z, a-z and 0-9.

function getRandomString(length) {
    let randomChars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    let result = '';
    for (let i = 0; i < length; i++) {
        result += randomChars.charAt(Math.floor(Math.random() * randomChars.length));
    }
    return result;
}

Step 2: Choose length for the string

Next, we choose the length of the random string from the parameters of the function.

getRandomString(10); // Generate a random string of 10 characters

Step 3: Use the function

We can now use this function in any project where we need a random string.

console.log(getRandomString(10)); //Example usage of the function

Step 4: Make it general

We can make this function more general by allowing the user to specify their own characters.

function getRandomString(length, characters) {
    let result = '';
    for (let i = 0; i < length; i++) {
        result += characters.charAt(Math.floor(Math.random() * characters.length));
    }
    return result;
}

Step 5: Conclusion

And there you have it! A simple, flexible function for generating random strings. We started with randomAlphaNumeric string, and then we extended the function to allow custom character sets.

Here's the full function for reference:

function getRandomString(length, characters) {
    let result = '';
    for (let i = 0; i < length; i++) {
        result += characters.charAt(Math.floor(Math.random() * characters.length));
    }
    return result;
}
getRandomString(10, 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789');