convertDecimalToHexadecimal()

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Step 1: Understanding the Problem

First, we needed to understand what hexadecimal is. The hexadecimal number system is a base 16 number system which uses 16 symbols to represent all its numbers, these being the numbers from 0 to 9 and letters from A to F.

Since hexadecimal is based 16, each digit in a hex number can have 16 possible values. Here's how they map to decimal values:

0 in decimal is 0 in hexadecimal, 1 in decimal is 1 in hexadecimal, ... 9 in decimal is 9 in hexadecimal, 10 in decimal is A in hexadecimal, 11 in decimal is B in hexadecimal, ... 15 in decimal is F in hexadecimal.

Also note that in JavaScript the built-in method 'toString' has an optional parameter called 'radix', which specifies the base of the number system to use. When we passed 16 as the argument, we could convert a decimal number into hexadecimal.

var decimalNumber = 10;
var hexadecimalNumber = decimalNumber.toString(16);
console.log(hexadecimalNumber);  // Output: "a"

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Step 2: Begin to Define the Function

Now that you understand the concept, let's start defining the function. We've learned that we can use the 'toString' method to convert our decimal number into hexadecimal. We'll define our function and pass in the decimal number as an argument. Then, we just call the 'toString' method on that number.

function convertDecimalToHexadecimal(decimalNumber) {
    var hexadecimalNumber = decimalNumber.toString(16);
}

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Step 3: Adding Error Handling

What if someone puts something that's not a decimal number into our function? Let's add some error handling to check if the input is a number.

function convertDecimalToHexadecimal(decimalNumber) {
    if (typeof(decimalNumber) !== 'number') {
        throw Error('Input must be a number');
    }

    var hexadecimalNumber = decimalNumber.toString(16);
}

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Step 4: Returning Result

Right now the function converts the number but it's not useful if it doesn't return any results. Let's add a return statement that returns the converted hex value.

function convertDecimalToHexadecimal(decimalNumber) {
    if (typeof(decimalNumber) !== 'number') {
        throw Error('Input must be a number');
    }

    var hexadecimalNumber = decimalNumber.toString(16);

    return hexadecimalNumber;
}

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Conclusion:

And now we have a functional JavaScript function that converts a given decimal number into a hexadecimal. If the function receives an input that is not a number, it will throw an error.

function convertDecimalToHexadecimal(decimalNumber) {
    if (typeof(decimalNumber) !== 'number') {
        throw Error('Input must be a number');
    }

    var hexadecimalNumber = decimalNumber.toString(16);

    return hexadecimalNumber;
}

console.log(convertDecimalToHexadecimal(16));  // Output: "10"

With this function, you can now easily convert any decimal numbers to hexadecimal in JavaScript.