function Client_SubscribeEmail() {    
    var emailField = document.getElementById("Client_txtEmail");
    var frmreg = document.getElementById("frmreg");
    if ((frmreg != null) && (emailField != null)) {
       
        if ((frmreg.email != null) && (frmreg.name != null)) {
            if (ValidateEmailAddr(emailField.value)) {
                frmreg.email.value = emailField.value;
                frmreg.name.value = emailField.value;
                frmreg.submit();               
            } else {
                alert("Please enter a valid email address");
            }
        }        
    }
}

function ValidateEmailAddr(str) {
    var at = "@";
    var dot = ".";
    var lat = str.indexOf(at);
    var lstr = str.length;
    var ldot = str.indexOf(dot);
    if (str.indexOf(at) == -1) {
        return false;
    }

    else if (str.indexOf(at) == -1 || str.indexOf(at) == 0 || str.indexOf(at) == lstr) {
        return false;
    }

    else if (str.indexOf(dot) == -1 || str.indexOf(dot) == 0 || str.indexOf(dot) == lstr) {
        return false;
    }

    else if (str.indexOf(at, (lat + 1)) != -1) {
        return false;
    }

    else if (str.substring(lat - 1, lat) == dot || str.substring(lat + 1, lat + 2) == dot) {
        return false;
    }

    else if (str.indexOf(dot, (lat + 2)) == -1) {
        return false;
    }

    else if (str.indexOf(" ") != -1) {
        return false;
    }
    else
        return true;
}