regex - HTML5 input validate letters and numbers

Question

I need a pattern for a HTML5 form.

• Lowercase letters accepted
• Uppercase letters accepted
• Numbers accepted
• Minus character accepted

HTML so far

<input type="text" pattern="[a-zA-Z0-9-]" required>

The code above does not work. I guess I'm close?

Answer 1

You are pretty close actually:

[a-zA-Z0-9-]+
            ^

You just needed this + plus quantifier, which tells the input field to accept one or more the characters you have listed in the character class [].