Evaluates the text in the assigned text box for errors, this is called during
validation. Returns true if there are errors, false if there are no errors or if the text
box couldn't be accessed (see remarks).
Declaration Syntax RemarksAccess the text box using Parent.FindControl(TextComponentID), so the TextComponentID
must be the ID of the text box and the text box and this control must be in the same
naming container (eg. page, user control, grid item).
This method fires the ValidatorNeedsText event, which allows you to pass the text to check.