Parsley.js - Validate optional input for only numbers

Question

I have a form that has one optional input and 3 required input fields. For the optional input I have the below markup:

Answer 1

You can use data-parsley-type="digits". Notice the use of type="text" instead of number.

This works if you only want to allow digits (not floats).

<input type="text" placeholder="0" min="0" max="20000" step="100" 
    data-parsley-validation-threshold="1" data-parsley-trigger="keyup" 
    data-parsley-type="digits" />

If you want floats, you can use data-parsley-type='number':

<input type="text" placeholder="0" min="0" max="20000" step="100" 
    data-parsley-validation-threshold="1" data-parsley-trigger="keyup" 
    data-parsley-type="number" />