发送和显示有关验证结果的信息的问题

I have user registration form that calls another file which calls an object that performs validation.

I would like to create this form to be sticky and display info about validation errors next to respective fields.

How can I resend data to the page with the form?

You could use client-side JavaScript validation (and back that up with server-side PHP validation too) but if you set the forms' POST target to be the same page that generates the form (so $_SERVER['REQUEST_URI']) you could call the validation object/class in a statement like:

if (isset($_POST['submit'])) {
    // Validation code
}

// Generate form along with any output from validation script