title: Javascript "if" statement within alert
body: <p>I'm new to JavaScript, and I'm wondering how to embed "if" statements within alerts.  Specifically, I'm working on a form, and I want the alert that appears after the user clicks "Submit" to display different messages depending on which elements of the user's input are problematic (if any).  I know that I could do it the other way around (i.e., use a series of if statements to determine which alert to show), but I was hoping to be able to use "if/else" within the alert code itself.  Thanks!</p>