Regex - How to allow white space comma and letters

Question

I'm trying to validate text field using JavaScript. It should allow (az, white space between words, and AZ).

I tried this but it doesn't work:

function formValidator(){
   var name = document.getElementById('name');

if(isAlphabet(name, "Please enter only letters for your  name")){
return true;
}
return false;
}
     function isAlphabet(elem, helperMsg){
        var alphaExp = /^[a-zA-Z.,\b]+$/;
        if(elem.value.match(alphaExp)){
            return true;
        }else{
            alert(helperMsg);
            elem.focus();
            return false;
        } 

Answer 1

I think your regex should look like this:

/^[a-z]+(\s+[a-z]+)*$/i

This allows AZ (case-insensitive because of /i ), followed by any amount of white-space characters and AZ again. The last part may be repeated or doesn't need to be present at all.

Answer 2

单词之间只能有一个空格：

/^[a-z]+( [a-z]+)*$/i.test(str);