I have searched through the forums but can't find quite what I need. I have a form that needs to verify the email address with specific requirements... the email field should have only one '@' in it and may contain letters, numbers, and the following characters: hyphen, underscore and period.
Also, the first character must be a letter. If this field fails these validations, it will display an alert box informing the user of the specific error and place the focus on the Email Id field with the text selected.

I have figured out how to make sure that the field isn't empty, but can't figure out the rest... any suggestion or help would be greatly appreciated

Code:
function validEmail()
{
     if (document.myForm.emailId.value == "")
    {
		alert("Please enter a valid email")
		return false;
    }	
return true;
}