Are Dashes Allowed In Javascript Property Names

Dashes in JavaScript Property Names

One of the questions that often pops up when working with JavaScript is whether or not you can use dashes in object property names. The short answer is that you can't use dashes directly in property names in JavaScript. However, there are workarounds that you can employ to achieve a similar result.

In JavaScript, object properties are identifiers and follow the same rules as variable names. This means that property names can only contain letters, numbers, and underscores. Dashes are not allowed in property names because they are interpreted as the subtraction operator in JavaScript.

So, how can you work around this limitation if you really need to use dashes in your property names? One common approach is to use bracket notation to access properties with dashes.

Let's say you have an object with a property name that includes a dash:

const myObject = {
  "first-name": "John",
  "last-name": "Doe"
};

To access the "first-name" property, you can use bracket notation:

console.log(myObject["first-name"]); // Output: John

Using square brackets allows you to access properties with special characters, including dashes. Although this method works, it is a bit more cumbersome than the dot notation typically used for accessing object properties.

Another approach is to use camel case instead of dashes. Camel case is a naming convention where each word in a compound word is capitalized except for the first word. For example:

const myObject = {
  firstName: "John",
  lastName: "Doe"
};

By using camel case, you can achieve a similar visual separation between words without using dashes. This is a common practice in JavaScript and can make your code easier to read and maintain.

If you are working with data that already uses dashes in property names and you cannot modify the data structure, you can write a function to convert property names with dashes to camel case for easier access. Here's an example of how you could achieve this:

function convertToCamelCase(obj) {
  const convertedObj = {};
  for (const key in obj) {
    if (obj.hasOwnProperty(key)) {
      const camelCaseKey = key.replace(/-([a-z])/g, function (g) { return g[1].toUpperCase(); });
      convertedObj[camelCaseKey] = obj[key];
    }
  }
  return convertedObj;
}

const myObject = {
  "first-name": "John",
  "last-name": "Doe"
};

const convertedObject = convertToCamelCase(myObject);
console.log(convertedObject.firstName); // Output: John

In conclusion, while dashes are not allowed in JavaScript property names, you can use bracket notation to access properties with dashes or consider using camel case as a naming convention to achieve a similar visual effect without breaking the rules of object property naming in JavaScript. Experiment with these methods to find the approach that works best for your specific use case.