javascript正则表达式验证，如果没有内容

Question

I have the following validation on a form field:

$(".controlsphone input").blur(function() {
    var ree = /^\d+$/;
    if(ree.test(document.getElementById("register_telephone").value))
        {
            $(this).css('border-color','green');
            $(this).siblings('.info').css('display','none');
            $(this).siblings('.error').css('display','none');
            $(this).siblings('.valid').css('display','inline-block');   
            $("#email_error401112").hide();
            $('#registerErrors').hide();
    }
    else
    {
        $('#registerErrors').show();
        $('#email_error401112').remove();
        $('#registerErrors').append('<p id="email_error401112">Please enter a phone number</p>');
    }
});

I would like to only validate the field if a number exists. The field is not required, but if there is content within the field, it needs to be valid (a number)

How does the above code look? Any ideas what i can do to implement this?

Cheers, Dan

Answer 1

Use

var ree = /^\d*$/;

because + stands for one or more, excluding zero.

while * stands for zero or more