JavaScript and DHTML Wizardry

Regular Expressions

function validEmail(email) {
    invalidChars = " /:,;"

    if (email == "") {
        return false
    }
    for (i=0; i<invalidChars.length; i++) {
        badChar = invalidChars.charAt(i)
        if (email.indexOf(badChar,0) > -1) {
            return false
        }
    }
    atPos = email.indexOf("@",1)
    if (atPos == -1) {
        return false
    }
    if (email.indexOf("@",atPos+1) > -1) {
        return false
    }
    periodPos = email.indexOf(".",atPos)
    if (periodPos == -1) {
        return false
    }
    if (periodPos+3 > email.length) {
        return false
    }
    return true
}