Question

I tested the following code and it returned me false when I expected it to be true..How can I fix this and why it’s returning me false?

<script type="text/javascript">

 var str3 ="-12346dsfs56";
var reg4 =/^(-{1})\d+$/;
alert(reg4.test(str3));
</script>

Answer 1

The regex returns False because that string is not a number (it contains letters)!

If you drop the $, the regex will only check if the string begins with a - and at least one digit. And you can drop the {1}, it’s unnecessary since one occurrence is the default for a regex token.