Evaluation for non-blank input but allowing for blank spaces

I'm validating for non-blank input, but I am allowing for spaces, so that typical English can be input.

I have this:

jQuery.valid开发者_JAVA技巧ator.addMethod("alphanumeric", function(value, element) {
            return this.optional(element) || (/^[a-zA-Z0-9]+/.test(value));
});

Which will accept strings that have no spaces, otherwise it will not accept them.

Ex: It will accept Stack or Overflow but not Stack Overflow

I want to check for "at least one alphanumeric character somewhere". How may I go about this?

Note: If I am going about this in a conceptually inefficient way, please correct me, surely there is a standardized way of validating like this.

jQuery.validator.addMethod("alphanumeric", function(value, element) {
            return this.optional(element) || (/^[a-zA-Z0-9]{1}([a-zA-Z0-9]*| [a-zA-Z0-9]+)*$/.test(value));
});

Must be this ;)

Edit: RegExp missing /