Question

function validEmail (emailAddress)
{
    for (var index=0; index < emailAddress.length; index++)
    {
        if ( emailAddress[index] == "@") 
        {
            for (var  count=0; count <emailAddress.length; count++)
            {
                if (emailAddress[count] == ".")
                {
                    return true;
                }
            }
        }
        else
        {
            return false;
        }
    }
}

function btnParseAddress_onclick()
{
    var emailAddress = addressTextbox.value;

    var userName = emailUsername(emailAddress);
    var domain = emailDomain (emailAddress);
    var valid = validEmail (emailAddress);

    if (valid)
    {
        outputTextbox.value = "Username:" + userName + "\nDomain:" + domain
    } 
    else
    {
        outputTextbox.value = "Invalid Email Address"
    }
}

Now the point of this assignment is to return a username and a domain from an inputted email address. I have deleted other functions and variables to help focus better on the problem.

I need to validate the email address first. I need to make sure there is an “@” and a “.” within the string entered and return the value with true or false. True having the strings and false not having the strings. When I run the file, the return value is always false. I can’t figure out if it is my for loop in the validEmail function or the if statement in btnParseAddress_onclick function

Answer 1

You can avoid the for loop by using IndexOf twice:

if (emailAddress.IndexOf('.', emailAddress.IndexOf('@')+1) > 0) {
    Console.WriteLine("The e-mail address looks valid.");
}