How to create COC for form methods , How to get formRun , How to make control visible false on form in D365FO

How to create COC for form method in D365FO

Example Code

[ExtensionOf(formStr(ProjInvoiceListPage))]
final class TestProjInvoiceListPage_Extension
{
    public void init()
    {
        next init();

        FormRun formRun = this as FormRun;

        if(ProjParameters::find().TestPrintPGGDesignForProjectInvoice)
        {
            FormControl         stdViewCopyBtn   = formrun.design(0).controlName('PrintProjInvoiceCopyButton');
            FormControl         stdViewOrigBtn   = formrun.design(0).controlName('PrintProjInvoiceButton');
            stdViewCopyBtn.visible(false);
            stdViewOrigBtn.visible(false);
        }
        else
        {
            FormControl         customViewCopyBtn   = formrun.design(0).controlName('TestPSAProjInvoiceCopy');
            FormControl         customViewOrigBtn   = formrun.design(0).controlName('TestPSAProjInvoiceOriginal');

            customViewCopyBtn.visible(true);
            customViewOrigBtn.visible(true);
        }
    }
}