Regex is Beautiful

Recently I was developing a game using Unity. At the start of the game, the player has to input a name. However, I wanted to restrict the player’s name to alphabetic only.

There are many ways to validate user input, but in this case, I decided to give regex a go. Here is the solution.

if (!Regex.IsMatch(userInput.text, "^[a-zA-Z]+$"))
{
    userMessage.text = "Invalid Input: only alphabets are allowed";
    return;
}

It’s all in this pattern “^[a-zA-Z]+$”, let have a look:

| ^        | assert the beginning of a line                       |
| [a-zA-Z] | means lower case and upper case are allowed          |
| +        | means match one or unlimited from the previous token |
| $        | assert the end of a line                             |

If you want to limit the length of the user to a maximum of 7, replace the + with {1,7}. This simple solution shows how regex is universal, beautiful, and efficient.